ALSA: hda - Add snd_hda_override_conn_list() helper function

Add a function to add/modify the connection-list cache entry.
It'll be useful to fix a buggy hardware result.

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

diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
index 7f8502388a822ec3c194f3b87847f67800b243f7..d0deab1ed510cbd5f02ad1b4a75258196a213c9f 100644 (file)
--- a/sound/pci/hda/hda_codec.c
+++ b/sound/pci/hda/hda_codec.c
@@ -310,10 +310,23 @@ EXPORT_SYMBOL_HDA(snd_hda_get_sub_nodes);
 
 static int _hda_get_connections(struct hda_codec *codec, hda_nid_t nid,
                                hda_nid_t *conn_list, int max_conns);
-static bool add_conn_list(struct snd_array *array, hda_nid_t nid);
+
+/* look up the cached results */
+static hda_nid_t *lookup_conn_list(struct snd_array *array, hda_nid_t nid)
+{
+       int i, len;
+       for (i = 0; i < array->used; ) {
+               hda_nid_t *p = snd_array_elem(array, i);
+               if (nid == *p)
+                       return p;
+               len = p[1];
+               i += len + 2;
+       }
+       return NULL;
+}
 
 /**
- * snd_hda_get_connections - get connection list
+ * snd_hda_get_conn_list - get connection list
  * @codec: the HDA codec
  * @nid: NID to parse
  * @listp: the pointer to store NID list
@@ -327,42 +340,31 @@ int snd_hda_get_conn_list(struct hda_codec *codec, hda_nid_t nid,
                          const hda_nid_t **listp)
 {
        struct snd_array *array = &codec->conn_lists;
-       int i, len, old_used;
+       int len, err;
        hda_nid_t list[HDA_MAX_CONNECTIONS];
        hda_nid_t *p;
+       bool added = false;
 
-       /* look up the cached results */
-       for (i = 0; i < array->used; ) {
-               p = snd_array_elem(array, i);
-               len = p[1];
-               if (nid == *p) {
-                       if (listp)
-                               *listp = p + 2;
-                       return len;
-               }
-               i += len + 2;
+ again:
+       /* if the connection-list is already cached, read it */
+       p = lookup_conn_list(array, nid);
+       if (p) {
+               if (listp)
+                       *listp = p + 2;
+               return p[1];
        }
+       if (snd_BUG_ON(added))
+               return -EINVAL;
 
+       /* read the connection and add to the cache */
        len = _hda_get_connections(codec, nid, list, HDA_MAX_CONNECTIONS);
        if (len < 0)
                return len;
-
-       /* add to the cache */
-       old_used = array->used;
-       if (!add_conn_list(array, nid) || !add_conn_list(array, len))
-               goto error_add;
-       for (i = 0; i < len; i++)
-               if (!add_conn_list(array, list[i]))
-                       goto error_add;
-
-       p = snd_array_elem(array, old_used);
-       if (listp)
-               *listp = p + 2;
-       return len;
-               
- error_add:
-       array->used = old_used;
-       return -ENOMEM;
+       err = snd_hda_override_conn_list(codec, nid, len, list);
+       if (err < 0)
+               return err;
+       added = true;
+       goto again;
 }
 EXPORT_SYMBOL_HDA(snd_hda_get_conn_list);
 
@@ -502,6 +504,43 @@ static bool add_conn_list(struct snd_array *array, hda_nid_t nid)
        return true;
 }
 
+/**
+ * snd_hda_override_conn_list - add/modify the connection-list to cache
+ * @codec: the HDA codec
+ * @nid: NID to parse
+ * @len: number of connection list entries
+ * @list: the list of connection entries
+ *
+ * Add or modify the given connection-list to the cache.  If the corresponding
+ * cache already exists, invalidate it and append a new one.
+ *
+ * Returns zero or a negative error code.
+ */
+int snd_hda_override_conn_list(struct hda_codec *codec, hda_nid_t nid, int len,
+                              const hda_nid_t *list)
+{
+       struct snd_array *array = &codec->conn_lists;
+       hda_nid_t *p;
+       int i, old_used;
+
+       p = lookup_conn_list(array, nid);
+       if (p)
+               *p = -1; /* invalidate the old entry */
+
+       old_used = array->used;
+       if (!add_conn_list(array, nid) || !add_conn_list(array, len))
+               goto error_add;
+       for (i = 0; i < len; i++)
+               if (!add_conn_list(array, list[i]))
+                       goto error_add;
+       return 0;
+
+ error_add:
+       array->used = old_used;
+       return -ENOMEM;
+}
+EXPORT_SYMBOL_HDA(snd_hda_override_conn_list);
+
 /**
  * snd_hda_get_conn_index - get the connection index of the given NID
  * @codec: the HDA codec

diff --git a/sound/pci/hda/hda_codec.h b/sound/pci/hda/hda_codec.h
index 10d500d2ba33fa51bd8743face2301f1169fb0e9..e6bc16f66bceeeaff375af566c65558f05753e51 100644 (file)
--- a/sound/pci/hda/hda_codec.h
+++ b/sound/pci/hda/hda_codec.h
@@ -905,6 +905,8 @@ int snd_hda_get_connections(struct hda_codec *codec, hda_nid_t nid,
                            hda_nid_t *conn_list, int max_conns);
 int snd_hda_get_conn_list(struct hda_codec *codec, hda_nid_t nid,
                          const hda_nid_t **listp);
+int snd_hda_override_conn_list(struct hda_codec *codec, hda_nid_t nid, int nums,
+                         const hda_nid_t *list);
 int snd_hda_get_conn_index(struct hda_codec *codec, hda_nid_t mux,
                           hda_nid_t nid, int recursive);
 int snd_hda_query_supported_pcm(struct hda_codec *codec, hda_nid_t nid,