[PATCH v9 04/12] virtio-sound: set PCM stream parameters

[Emmanouil Pitsidianakis]

This commit sets the virtio-snd device's default PCM parameters in
virtio_snd_pcm_set_params_impl(). The same function will be used to set
parameters from the guest with VIRTIO_SND_R_PCM_SET_PARAMS in a
follow-up commit.

PCM parameters describe the sound card parameters that the guest's
kernel sees as an ALSA device.

Based-on: 
https://github.com/OpenSynergy/qemu/commit/5a2f350eec5d157b90d9c7b40a8e603f4da92471
Signed-off-by: Igor Skalkin <Igor.Skalkin@opensynergy.com>
Signed-off-by: Anton Yakovlev <Anton.Yakovlev@opensynergy.com>
Signed-off-by: Emmanouil Pitsidianakis <manos.pitsidianakis@linaro.org>
---
 hw/virtio/virtio-snd.c | 266 +++++++++++++++++++++++++++++++++++++++--
 1 file changed, 258 insertions(+), 8 deletions(-)

diff --git a/hw/virtio/virtio-snd.c b/hw/virtio/virtio-snd.c
index cb5573935d..dea4ce6305 100644
--- a/hw/virtio/virtio-snd.c
+++ b/hw/virtio/virtio-snd.c
@@ -32,6 +32,29 @@
 #define VIRTIO_SOUND_CHMAP_DEFAULT 0
 #define VIRTIO_SOUND_HDA_FN_NID 0
 
+static uint32_t supported_formats = BIT(VIRTIO_SND_PCM_FMT_S8)
+                                  | BIT(VIRTIO_SND_PCM_FMT_U8)
+                                  | BIT(VIRTIO_SND_PCM_FMT_S16)
+                                  | BIT(VIRTIO_SND_PCM_FMT_U16)
+                                  | BIT(VIRTIO_SND_PCM_FMT_S32)
+                                  | BIT(VIRTIO_SND_PCM_FMT_U32)
+                                  | BIT(VIRTIO_SND_PCM_FMT_FLOAT);
+
+static uint32_t supported_rates = BIT(VIRTIO_SND_PCM_RATE_5512)
+                                | BIT(VIRTIO_SND_PCM_RATE_8000)
+                                | BIT(VIRTIO_SND_PCM_RATE_11025)
+                                | BIT(VIRTIO_SND_PCM_RATE_16000)
+                                | BIT(VIRTIO_SND_PCM_RATE_22050)
+                                | BIT(VIRTIO_SND_PCM_RATE_32000)
+                                | BIT(VIRTIO_SND_PCM_RATE_44100)
+                                | BIT(VIRTIO_SND_PCM_RATE_48000)
+                                | BIT(VIRTIO_SND_PCM_RATE_64000)
+                                | BIT(VIRTIO_SND_PCM_RATE_88200)
+                                | BIT(VIRTIO_SND_PCM_RATE_96000)
+                                | BIT(VIRTIO_SND_PCM_RATE_176400)
+                                | BIT(VIRTIO_SND_PCM_RATE_192000)
+                                | BIT(VIRTIO_SND_PCM_RATE_384000);
+
 static const VMStateDescription vmstate_virtio_snd_device = {
     .name = TYPE_VIRTIO_SND,
     .version_id = VIRTIO_SOUND_VM_VERSION,
@@ -97,6 +120,215 @@ virtio_snd_ctrl_cmd_free(virtio_snd_ctrl_command *cmd)
     g_free(cmd);
 }
 
+/*
+ * Get a specific stream from the virtio sound card device.
+ * Returns NULL if @stream_id is invalid or not allocated.
+ *
+ * @s: VirtIOSound device
+ * @stream_id: stream id
+ */
+static VirtIOSoundPCMStream *virtio_snd_pcm_get_stream(VirtIOSound *s,
+                                                       uint32_t stream_id)
+{
+    return stream_id >= s->snd_conf.streams ? NULL :
+        s->pcm->streams[stream_id];
+}
+
+/*
+ * Get params for a specific stream.
+ *
+ * @s: VirtIOSound device
+ * @stream_id: stream id
+ */
+static virtio_snd_pcm_set_params *virtio_snd_pcm_get_params(VirtIOSound *s,
+                                                            uint32_t stream_id)
+{
+    return stream_id >= s->snd_conf.streams ? NULL
+        : &s->pcm->pcm_params[stream_id];
+}
+
+/*
+ * Set the given stream params.
+ * Called by both virtio_snd_handle_pcm_set_params and during device
+ * initialization.
+ * Returns the response status code. (VIRTIO_SND_S_*).
+ *
+ * @s: VirtIOSound device
+ * @params: The PCM params as defined in the virtio specification
+ */
+static
+uint32_t virtio_snd_set_pcm_params(VirtIOSound *s,
+                                   uint32_t stream_id,
+                                   virtio_snd_pcm_set_params *params)
+{
+    virtio_snd_pcm_set_params *st_params;
+
+    if (stream_id >= s->snd_conf.streams || !(s->pcm->pcm_params)) {
+        virtio_error(VIRTIO_DEVICE(s), "Streams have not been initialized.\n");
+        return cpu_to_le32(VIRTIO_SND_S_BAD_MSG);
+    }
+
+    st_params = virtio_snd_pcm_get_params(s, stream_id);
+
+    if (params->channels < 1 || params->channels > AUDIO_MAX_CHANNELS) {
+        error_report("Number of channels is not supported.");
+        return cpu_to_le32(VIRTIO_SND_S_NOT_SUPP);
+    }
+    if (!(supported_formats & BIT(params->format))) {
+        error_report("Stream format is not supported.");
+        return cpu_to_le32(VIRTIO_SND_S_NOT_SUPP);
+    }
+    if (!(supported_rates & BIT(params->rate))) {
+        error_report("Stream rate is not supported.");
+        return cpu_to_le32(VIRTIO_SND_S_NOT_SUPP);
+    }
+
+    st_params->buffer_bytes = le32_to_cpu(params->buffer_bytes);
+    st_params->period_bytes = le32_to_cpu(params->period_bytes);
+    st_params->features = le32_to_cpu(params->features);
+    st_params->channels = params->channels;
+    st_params->format = params->format;
+    st_params->rate = params->rate;
+
+    return cpu_to_le32(VIRTIO_SND_S_OK);
+}
+
+/*
+ * Get a QEMU Audiosystem compatible format value from a VIRTIO_SND_PCM_FMT_*
+ */
+static AudioFormat virtio_snd_get_qemu_format(uint32_t format)
+{
+    #define CASE(FMT)               \
+    case VIRTIO_SND_PCM_FMT_##FMT:  \
+        return AUDIO_FORMAT_##FMT;
+
+    switch (format) {
+    CASE(U8)
+    CASE(S8)
+    CASE(U16)
+    CASE(S16)
+    CASE(U32)
+    CASE(S32)
+    case VIRTIO_SND_PCM_FMT_FLOAT:
+        return AUDIO_FORMAT_F32;
+    default:
+        g_assert_not_reached();
+    }
+
+    #undef CASE
+}
+
+/*
+ * Get a QEMU Audiosystem compatible frequency value from a
+ * VIRTIO_SND_PCM_RATE_*
+ */
+static uint32_t virtio_snd_get_qemu_freq(uint32_t rate)
+{
+    #define CASE(RATE)               \
+    case VIRTIO_SND_PCM_RATE_##RATE: \
+        return RATE;
+
+    switch (rate) {
+    CASE(5512)
+    CASE(8000)
+    CASE(11025)
+    CASE(16000)
+    CASE(22050)
+    CASE(32000)
+    CASE(44100)
+    CASE(48000)
+    CASE(64000)
+    CASE(88200)
+    CASE(96000)
+    CASE(176400)
+    CASE(192000)
+    CASE(384000)
+    default:
+        g_assert_not_reached();
+    }
+
+    #undef CASE
+}
+
+/*
+ * Get QEMU Audiosystem compatible audsettings from virtio based pcm stream
+ * params.
+ */
+static void virtio_snd_get_qemu_audsettings(audsettings *as,
+                                            virtio_snd_pcm_set_params *params)
+{
+    as->nchannels = MIN(AUDIO_MAX_CHANNELS, params->channels);
+    as->fmt = virtio_snd_get_qemu_format(params->format);
+    as->freq = virtio_snd_get_qemu_freq(params->rate);
+    as->endianness = target_words_bigendian() ? 1 : 0;
+}
+
+/*
+ * Close a stream and free all its resources.
+ *
+ * @stream: VirtIOSoundPCMStream *stream
+ */
+static void virtio_snd_pcm_close(VirtIOSoundPCMStream *stream)
+{
+}
+
+/*
+ * Prepares a VirtIOSound card stream.
+ * Returns the response status code. (VIRTIO_SND_S_*).
+ *
+ * @s: VirtIOSound device
+ * @stream_id: stream id
+ */
+static uint32_t virtio_snd_pcm_prepare(VirtIOSound *s, uint32_t stream_id)
+{
+    audsettings as;
+    virtio_snd_pcm_set_params *params;
+    VirtIOSoundPCMStream *stream;
+
+    if (!s->pcm->streams ||
+        !s->pcm->pcm_params ||
+        stream_id >= s->snd_conf.streams) {
+        return cpu_to_le32(VIRTIO_SND_S_BAD_MSG);
+    }
+
+    params = virtio_snd_pcm_get_params(s, stream_id);
+    if (!params) {
+        return cpu_to_le32(VIRTIO_SND_S_BAD_MSG);
+    }
+
+    stream = virtio_snd_pcm_get_stream(s, stream_id);
+    virtio_snd_pcm_close(stream);
+    if (!stream) {
+        stream = g_new0(VirtIOSoundPCMStream, 1);
+        stream->id = stream_id;
+        stream->pcm = s->pcm;
+        stream->s = s;
+        qemu_mutex_init(&stream->queue_mutex);
+        QSIMPLEQ_INIT(&stream->queue);
+
+        s->pcm->streams[stream_id] = stream;
+    }
+
+    virtio_snd_get_qemu_audsettings(&as, params);
+    stream->info.direction = stream_id < s->snd_conf.streams / 2 +
+        (s->snd_conf.streams & 1) ? VIRTIO_SND_D_OUTPUT : VIRTIO_SND_D_INPUT;
+    stream->info.hdr.hda_fn_nid = VIRTIO_SOUND_HDA_FN_NID;
+    stream->info.features = 0;
+    stream->info.channels_min = 1;
+    stream->info.channels_max = as.nchannels;
+    stream->info.formats = supported_formats;
+    stream->info.rates = supported_rates;
+
+    stream->params.buffer_bytes = params->buffer_bytes;
+    stream->params.period_bytes = params->period_bytes;
+
+    stream->positions[0] = VIRTIO_SND_CHMAP_FL;
+    stream->positions[1] = VIRTIO_SND_CHMAP_FR;
+    stream->as = as;
+
+    return cpu_to_le32(VIRTIO_SND_S_OK);
+}
+
 static const char *print_code(uint32_t code)
 {
     #define CASE(CODE)            \
@@ -298,6 +530,8 @@ static void virtio_snd_realize(DeviceState *dev, Error 
**errp)
     ERRP_GUARD();
     VirtIOSound *vsnd = VIRTIO_SND(dev);
     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+    virtio_snd_pcm_set_params default_params = { 0 };
+    uint32_t status;
 
     vsnd->pcm = NULL;
     vsnd->vmstate =
@@ -336,6 +570,13 @@ static void virtio_snd_realize(DeviceState *dev, Error 
**errp)
 
     AUD_register_card("virtio-sound", &vsnd->card);
 
+    /* set default params for all streams */
+    default_params.features = 0;
+    default_params.buffer_bytes = 8192;
+    default_params.period_bytes = 2048;
+    default_params.channels = 2;
+    default_params.format = VIRTIO_SND_PCM_FMT_S16;
+    default_params.rate = VIRTIO_SND_PCM_RATE_48000;
     vsnd->queues[VIRTIO_SND_VQ_CONTROL] =
         virtio_add_queue(vdev, 64, virtio_snd_handle_ctrl);
     vsnd->queues[VIRTIO_SND_VQ_EVENT] =
@@ -346,15 +587,23 @@ static void virtio_snd_realize(DeviceState *dev, Error 
**errp)
         virtio_add_queue(vdev, 64, virtio_snd_handle_xfer);
     qemu_mutex_init(&vsnd->cmdq_mutex);
     QTAILQ_INIT(&vsnd->cmdq);
-}
 
-/*
- * Close the stream and free its resources.
- *
- * @stream: VirtIOSoundPCMStream *stream
- */
-static void virtio_snd_pcm_close(VirtIOSoundPCMStream *stream)
-{
+    for (uint32_t i = 0; i < vsnd->snd_conf.streams; i++) {
+        status = virtio_snd_set_pcm_params(vsnd, i, &default_params);
+        if (status != cpu_to_le32(VIRTIO_SND_S_OK)) {
+            error_setg(errp,
+                       "Can't initalize stream params, device responded with 
%s.",
+                       print_code(status));
+            return;
+        }
+        status = virtio_snd_pcm_prepare(vsnd, i);
+        if (status != cpu_to_le32(VIRTIO_SND_S_OK)) {
+            error_setg(errp,
+                       "Can't prepare streams, device responded with %s.",
+                       print_code(status));
+            return;
+        }
+    }
 }
 
 static void virtio_snd_unrealize(DeviceState *dev)
@@ -373,6 +622,7 @@ static void virtio_snd_unrealize(DeviceState *dev)
                 if (stream) {
                     virtio_snd_process_cmdq(stream->s);
                     virtio_snd_pcm_close(stream);
+                    qemu_mutex_destroy(&stream->queue_mutex);
                     g_free(stream);
                 }
             }
-- 
2.39.2