1 files changed, 59 insertions, 49 deletions

diff --git a/src/modules/alsa/alsa-mixer.c b/src/modules/alsa/alsa-mixer.c
index 3eef5f9c..51a6cd64 100644
--- a/src/modules/alsa/alsa-mixer.c
+++ b/src/modules/alsa/alsa-mixer.c
@@ -1084,10 +1084,14 @@ int pa_alsa_path_set_mute(pa_alsa_path *p, snd_mixer_t *m, pa_bool_t muted) {
     return 0;
 }
 
-static int element_mute_volume(pa_alsa_element *e, snd_mixer_t *m) {
-    snd_mixer_elem_t *me;
-    snd_mixer_selem_id_t *sid;
-    int r;
+/* Depending on whether e->volume_use is _OFF, _ZERO or _CONSTANT, this
+ * function sets all channels of the volume element to e->min_volume, 0 dB or
+ * e->constant_volume. */
+static int element_set_constant_volume(pa_alsa_element *e, snd_mixer_t *m) {
+    snd_mixer_elem_t *me = NULL;
+    snd_mixer_selem_id_t *sid = NULL;
+    int r = 0;
+    long volume = -1;
 
     pa_assert(m);
     pa_assert(e);
@@ -1098,49 +1102,44 @@ static int element_mute_volume(pa_alsa_element *e, snd_mixer_t *m) {
         return -1;
     }
 
-    if (e->direction == PA_ALSA_DIRECTION_OUTPUT)
-        r = snd_mixer_selem_set_playback_volume_all(me, e->min_volume);
-    else
-        r = snd_mixer_selem_set_capture_volume_all(me, e->min_volume);
-
-    if (r < 0)
-        pa_log_warn("Failed to set volume to muted of %s: %s", e->alsa_name, pa_alsa_strerror(errno));
+    switch (e->volume_use) {
+        case PA_ALSA_VOLUME_OFF:
+            volume = e->min_volume;
+            break;
 
-    return r;
-}
+        case PA_ALSA_VOLUME_ZERO:
+            if (e->db_fix) {
+                long dB = 0;
 
-/* The volume to 0dB */
-static int element_zero_volume(pa_alsa_element *e, snd_mixer_t *m) {
-    snd_mixer_elem_t *me;
-    snd_mixer_selem_id_t *sid;
-    int r;
+                volume = decibel_fix_get_step(e->db_fix, &dB, +1);
+            }
+            break;
 
-    pa_assert(m);
-    pa_assert(e);
+        case PA_ALSA_VOLUME_CONSTANT:
+            volume = e->constant_volume;
+            break;
 
-    SELEM_INIT(sid, e->alsa_name);
-    if (!(me = snd_mixer_find_selem(m, sid))) {
-        pa_log_warn("Element %s seems to have disappeared.", e->alsa_name);
-        return -1;
+        default:
+            pa_assert_not_reached();
     }
 
-    if (e->direction == PA_ALSA_DIRECTION_OUTPUT)
-        if (e->db_fix) {
-            long value = 0;
+    if (volume >= 0) {
+        if (e->direction == PA_ALSA_DIRECTION_OUTPUT)
+            r = snd_mixer_selem_set_playback_volume_all(me, volume);
+        else
+            r = snd_mixer_selem_set_capture_volume_all(me, volume);
+    } else {
+        pa_assert(e->volume_use == PA_ALSA_VOLUME_ZERO);
+        pa_assert(!e->db_fix);
 
-            r = snd_mixer_selem_set_playback_volume_all(me, decibel_fix_get_step(e->db_fix, &value, +1));
-        } else
+        if (e->direction == PA_ALSA_DIRECTION_OUTPUT)
             r = snd_mixer_selem_set_playback_dB_all(me, 0, +1);
-    else
-        if (e->db_fix) {
-            long value = 0;
-
-            r = snd_mixer_selem_set_capture_volume_all(me, decibel_fix_get_step(e->db_fix, &value, +1));
-        } else
+        else
             r = snd_mixer_selem_set_capture_dB_all(me, 0, +1);
+    }
 
     if (r < 0)
-        pa_log_warn("Failed to set volume to 0dB of %s: %s", e->alsa_name, pa_alsa_strerror(errno));
+        pa_log_warn("Failed to set volume of %s: %s", e->alsa_name, pa_alsa_strerror(errno));
 
     return r;
 }
@@ -1178,11 +1177,9 @@ int pa_alsa_path_select(pa_alsa_path *p, snd_mixer_t *m) {
 
         switch (e->volume_use) {
             case PA_ALSA_VOLUME_OFF:
-                r = element_mute_volume(e, m);
-                break;
-
             case PA_ALSA_VOLUME_ZERO:
-                r = element_zero_volume(e, m);
+            case PA_ALSA_VOLUME_CONSTANT:
+                r = element_set_constant_volume(e, m);
                 break;
 
             case PA_ALSA_VOLUME_MERGE:
@@ -1368,6 +1365,12 @@ static int element_probe(pa_alsa_element *e, snd_mixer_t *m) {
                 pa_log_warn("Your kernel driver is broken: it reports a volume range from %li to %li which makes no sense.", e->min_volume, e->max_volume);
                 e->volume_use = PA_ALSA_VOLUME_IGNORE;
 
+            } else if (e->volume_use == PA_ALSA_VOLUME_CONSTANT &&
+                       (e->min_volume > e->constant_volume || e->max_volume < e->constant_volume)) {
+                pa_log_warn("Constant volume %li configured for element %s, but the available range is from %li to %li.",
+                            e->constant_volume, e->alsa_name, e->min_volume, e->max_volume);
+                e->volume_use = PA_ALSA_VOLUME_IGNORE;
+
             } else {
                 pa_bool_t is_mono;
                 pa_channel_position_t p;
@@ -1685,8 +1688,15 @@ static int element_parse_volume(
     else if (pa_streq(rvalue, "zero"))
         e->volume_use = PA_ALSA_VOLUME_ZERO;
     else {
-        pa_log("[%s:%u] Volume invalid of '%s'", filename, line, section);
-        return -1;
+        uint32_t constant;
+
+        if (pa_atou(rvalue, &constant) >= 0) {
+            e->volume_use = PA_ALSA_VOLUME_CONSTANT;
+            e->constant_volume = constant;
+        } else {
+            pa_log("[%s:%u] Volume invalid of '%s'", filename, line, section);
+            return -1;
+        }
     }
 
     return 0;
@@ -2637,7 +2647,7 @@ pa_alsa_path_set *pa_alsa_path_set_new(pa_alsa_mapping *m, pa_alsa_direction_t d
             pa_bool_t duplicate = FALSE;
             char **kn, *fn;
 
-            for (kn = pn; kn != in; kn++)
+            for (kn = pn; kn < in; kn++)
                 if (pa_streq(*kn, *in)) {
                     duplicate = TRUE;
                     break;
@@ -3669,14 +3679,14 @@ void pa_alsa_decibel_fix_dump(pa_alsa_decibel_fix *db_fix) {
 
     if (db_fix->db_values) {
         pa_strbuf *buf;
-        long i;
-        long max_i = db_fix->max_step - db_fix->min_step;
+        unsigned long i, nsteps;
 
-        buf = pa_strbuf_new();
-        pa_strbuf_printf(buf, "[%li]:%0.2f", db_fix->min_step, db_fix->db_values[0] / 100.0);
+        pa_assert(db_fix->min_step <= db_fix->max_step);
+        nsteps = db_fix->max_step - db_fix->min_step + 1;
 
-        for (i = 1; i <= max_i; ++i)
-            pa_strbuf_printf(buf, " [%li]:%0.2f", i + db_fix->min_step, db_fix->db_values[i] / 100.0);
+        buf = pa_strbuf_new();
+        for (i = 0; i < nsteps; ++i)
+            pa_strbuf_printf(buf, "[%li]:%0.2f ", i + db_fix->min_step, db_fix->db_values[i] / 100.0);
 
         db_values = pa_strbuf_tostring_free(buf);
     }