audio: mixer: change logic for AOs with no volume control

The volume filter was automatically inserted if setting AO volume
failed. Remove that logic, and instead enable softvol mode fully if
querying current volume (which will happen before any set attempts)
fails. Fully switching to softvol mode is more robust, and any case
where the behavior would differ (the behavior is neither that both
querying/setting always work nor that both always fail) would have
been buggy.

1 files changed, 27 insertions, 24 deletions

diff --git a/mixer.c b/mixer.c
index 25fb79f76c..0c92447c62 100644
--- a/mixer.c
+++ b/mixer.c
@@ -35,6 +35,7 @@ static void checkvolume(struct mixer *mixer)
     ao_control_vol_t vol;
     if (mixer->softvol || CONTROL_OK != ao_control(mixer->ao,
                                                 AOCONTROL_GET_VOLUME, &vol)) {
+        mixer->softvol = true;
         if (!mixer->afilter)
             return;
         float db_vals[AF_NCH];
@@ -74,35 +75,37 @@ void mixer_getvolume(mixer_t *mixer, float *l, float *r)
 static void setvolume_internal(mixer_t *mixer, float l, float r)
 {
     struct ao_control_vol vol = {.left = l, .right = r};
-    if (mixer->softvol || CONTROL_OK != ao_control(mixer->ao,
-                                                AOCONTROL_SET_VOLUME, &vol)) {
-        // af_volume uses values in dB
-        float db_vals[AF_NCH];
-        int i;
-        db_vals[0] = (l / 100.0) * (mixer->softvol_max / 100.0);
-        db_vals[1] = (r / 100.0) * (mixer->softvol_max / 100.0);
-        for (i = 2; i < AF_NCH; i++)
-            db_vals[i] = ((l + r) / 100.0) * (mixer->softvol_max / 100.0) / 2.0;
-        af_to_dB(AF_NCH, db_vals, db_vals, 20.0);
-        if (!af_control_any_rev(mixer->afilter,
-                AF_CONTROL_VOLUME_LEVEL | AF_CONTROL_SET, db_vals)) {
-            mp_tmsg(MSGT_GLOBAL, MSGL_INFO,
-                    "[Mixer] No hardware mixing, inserting volume filter.\n");
-            if (af_add(mixer->afilter, "volume")) {
-                if (!af_control_any_rev(mixer->afilter,
-                           AF_CONTROL_VOLUME_LEVEL|AF_CONTROL_SET, db_vals)) {
-                    mp_tmsg(MSGT_GLOBAL, MSGL_ERR,
-                            "[Mixer] No volume control available.\n");
-                    return;
-                }
-            }
-        }
+    if (!mixer->softvol) {
+        if (ao_control(mixer->ao, AOCONTROL_SET_VOLUME, &vol) != CONTROL_OK)
+            mp_tmsg(MSGT_GLOBAL, MSGL_ERR,
+                    "[Mixer] Failed to change audio output volume.\n");
+        return;
+    }
+    // af_volume uses values in dB
+    float db_vals[AF_NCH];
+    int i;
+    db_vals[0] = (l / 100.0) * (mixer->softvol_max / 100.0);
+    db_vals[1] = (r / 100.0) * (mixer->softvol_max / 100.0);
+    for (i = 2; i < AF_NCH; i++)
+        db_vals[i] = ((l + r) / 100.0) * (mixer->softvol_max / 100.0) / 2.0;
+    af_to_dB(AF_NCH, db_vals, db_vals, 20.0);
+    if (!af_control_any_rev(mixer->afilter,
+                            AF_CONTROL_VOLUME_LEVEL | AF_CONTROL_SET,
+                            db_vals)) {
+        mp_tmsg(MSGT_GLOBAL, MSGL_INFO,
+                "[Mixer] No hardware mixing, inserting volume filter.\n");
+        if (!(af_add(mixer->afilter, "volume")
+              && af_control_any_rev(mixer->afilter,
+                                    AF_CONTROL_VOLUME_LEVEL | AF_CONTROL_SET,
+                                    db_vals)))
+            mp_tmsg(MSGT_GLOBAL, MSGL_ERR,
+                    "[Mixer] No volume control available.\n");
     }
 }
 
 void mixer_setvolume(mixer_t *mixer, float l, float r)
 {
-    checkvolume(mixer);  // to check mute status
+    checkvolume(mixer);  // to check mute status and AO support for volume
     mixer->vol_l = av_clip(l, 0, 100);
     mixer->vol_r = av_clip(r, 0, 100);
     if (!mixer->ao || mixer->muted)