ALSA: hda - Add generic arrays

Added helper functions to handle generic arrays.

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

2 files changed, 54 insertions, 0 deletions

diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
index 19b4530e3baf..e70303183c3c 100644
--- a/sound/pci/hda/hda_codec.c
+++ b/sound/pci/hda/hda_codec.c
@@ -3196,3 +3196,37 @@ int snd_hda_codecs_inuse(struct hda_bus *bus)
 }
 #endif
 #endif
+
+/*
+ * generic arrays
+ */
+
+/* get a new element from the given array
+ * if it exceeds the pre-allocated array size, re-allocate the array
+ */
+void *snd_array_new(struct snd_array *array)
+{
+        if (array->used >= array->alloced) {
+                int num = array->alloced + array->alloc_align;
+                void *nlist = kcalloc(num + 1, array->elem_size, GFP_KERNEL);
+                if (!nlist)
+                        return NULL;
+                if (array->list) {
+                        memcpy(nlist, array->list,
+                               array->elem_size * array->alloced);
+                        kfree(array->list);
+                }
+                array->list = nlist;
+                array->alloced = num;
+        }
+        return array->list + (array->used++ * array->elem_size);
+}
+
+/* free the given array elements */
+void snd_array_free(struct snd_array *array)
+{
+        kfree(array->list);
+        array->used = 0;
+        array->alloced = 0;
+        array->list = NULL;
+}
diff --git a/sound/pci/hda/hda_codec.h b/sound/pci/hda/hda_codec.h
index 70e8fa09273d..b9b21766b730 100644
--- a/sound/pci/hda/hda_codec.h
+++ b/sound/pci/hda/hda_codec.h
@@ -520,6 +520,26 @@ enum {
 #define HDA_MAX_CODEC_ADDRESS   0x0f
 
 /*
+ * generic arrays
+ */
+struct snd_array {
+        unsigned int used;
+        unsigned int alloced;
+        unsigned int elem_size;
+        unsigned int alloc_align;
+        void *list;
+};
+
+void *snd_array_new(struct snd_array *array);
+void snd_array_free(struct snd_array *array);
+static inline void snd_array_init(struct snd_array *array, unsigned int size,
+                                  unsigned int align)
+{
+        array->elem_size = size;
+        array->alloc_align = align;
+}
+
+/*
  * Structures
  */