From fce93eb6254a12ff16b20426017efd540b982ef7 Mon Sep 17 00:00:00 2001 From: Tanu Kaskinen Date: Tue, 22 Mar 2011 12:23:19 +0200 Subject: alsa-mixer: Check that the kernel driver returns consistent limits with both snd_mixer_selem_get_*_dB_range() and _ask_*_vol_dB(). The check is inspired by a driver that returned higher dB limit from snd_mixer_selem_get_playback_dB_range() than what _ask_playback_vol_dB() returned at maximum integer volume. --- src/modules/alsa/alsa-mixer.c | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) (limited to 'src/modules') diff --git a/src/modules/alsa/alsa-mixer.c b/src/modules/alsa/alsa-mixer.c index b1340681..f236da0e 100644 --- a/src/modules/alsa/alsa-mixer.c +++ b/src/modules/alsa/alsa-mixer.c @@ -1398,6 +1398,43 @@ static int element_probe(pa_alsa_element *e, snd_mixer_t *m) { else e->has_dB = snd_mixer_selem_get_capture_dB_range(me, &min_dB, &max_dB) >= 0; + /* Check that the kernel driver returns consistent limits with + * both _get_*_dB_range() and _ask_*_vol_dB(). */ + if (e->has_dB && !e->db_fix) { + long min_dB_checked = 0; + long max_dB_checked = 0; + + if (e->direction == PA_ALSA_DIRECTION_OUTPUT) + r = snd_mixer_selem_ask_playback_vol_dB(me, e->min_volume, &min_dB_checked); + else + r = snd_mixer_selem_ask_capture_vol_dB(me, e->min_volume, &min_dB_checked); + + if (r < 0) { + pa_log_warn("Failed to query the dB value for %s at volume level %li", e->alsa_name, e->min_volume); + return -1; + } + + if (e->direction == PA_ALSA_DIRECTION_OUTPUT) + r = snd_mixer_selem_ask_playback_vol_dB(me, e->max_volume, &max_dB_checked); + else + r = snd_mixer_selem_ask_capture_vol_dB(me, e->max_volume, &max_dB_checked); + + if (r < 0) { + pa_log_warn("Failed to query the dB value for %s at volume level %li", e->alsa_name, e->max_volume); + return -1; + } + + if (min_dB != min_dB_checked || max_dB != max_dB_checked) { + pa_log_warn("Your kernel driver is broken: the reported dB range for %s (from %0.2f dB to %0.2f dB) " + "doesn't match the dB values at minimum and maximum volume levels: %0.2f dB at level %li, " + "%0.2f dB at level %li.", + e->alsa_name, + min_dB / 100.0, max_dB / 100.0, + min_dB_checked / 100.0, e->min_volume, max_dB_checked / 100.0, e->max_volume); + return -1; + } + } + if (e->has_dB) { #ifdef HAVE_VALGRIND_MEMCHECK_H VALGRIND_MAKE_MEM_DEFINED(&min_dB, sizeof(min_dB)); -- cgit