diff --git a/libavcodec/libgsmdec.c b/libavcodec/libgsmdec.c
index ae4a952d99..aa028bc262 100644
--- a/libavcodec/libgsmdec.c
+++ b/libavcodec/libgsmdec.c
@@ -48,8 +48,8 @@ typedef struct LibGSMDecodeContext {
 static av_cold int libgsm_decode_init(AVCodecContext *avctx) {
     LibGSMDecodeContext *s = avctx->priv_data;
 
-    avctx->channels       = 1;
-    avctx->channel_layout = AV_CH_LAYOUT_MONO;
+    av_channel_layout_uninit(&avctx->ch_layout);
+    avctx->ch_layout      = (AVChannelLayout)AV_CHANNEL_LAYOUT_MONO;
     if (!avctx->sample_rate)
         avctx->sample_rate = 8000;
     avctx->sample_fmt     = AV_SAMPLE_FMT_S16;
diff --git a/libavcodec/libgsmenc.c b/libavcodec/libgsmenc.c
index a2f6c1c62e..4f473b7cd3 100644
--- a/libavcodec/libgsmenc.c
+++ b/libavcodec/libgsmenc.c
@@ -49,12 +49,6 @@ static av_cold int libgsm_encode_close(AVCodecContext *avctx) {
 }
 
 static av_cold int libgsm_encode_init(AVCodecContext *avctx) {
-    if (avctx->channels > 1) {
-        av_log(avctx, AV_LOG_ERROR, "Mono required for GSM, got %d channels\n",
-               avctx->channels);
-        return -1;
-    }
-
     if (avctx->sample_rate != 8000) {
         av_log(avctx, AV_LOG_ERROR, "Sample rate 8000Hz required for GSM, got %dHz\n",
                avctx->sample_rate);
@@ -132,7 +126,10 @@ const AVCodec ff_libgsm_encoder = {
     .encode2        = libgsm_encode_frame,
     .close          = libgsm_encode_close,
     .defaults       = libgsm_defaults,
+#if FF_API_OLD_CHANNEL_LAYOUT
     .channel_layouts= (const uint64_t[]) { AV_CH_LAYOUT_MONO, 0 },
+#endif
+    .ch_layouts     = (const AVChannelLayout[]) { AV_CHANNEL_LAYOUT_MONO, { 0 } },
     .sample_fmts    = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16,
                                                      AV_SAMPLE_FMT_NONE },
     .wrapper_name   = "libgsm",
@@ -149,7 +146,10 @@ const AVCodec ff_libgsm_ms_encoder = {
     .encode2        = libgsm_encode_frame,
     .close          = libgsm_encode_close,
     .defaults       = libgsm_defaults,
+#if FF_API_OLD_CHANNEL_LAYOUT
     .channel_layouts= (const uint64_t[]) { AV_CH_LAYOUT_MONO, 0 },
+#endif
+    .ch_layouts     = (const AVChannelLayout[]) { AV_CHANNEL_LAYOUT_MONO, { 0 } },
     .sample_fmts    = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16,
                                                      AV_SAMPLE_FMT_NONE },
     .wrapper_name   = "libgsm",