diff options
Diffstat (limited to 'src/output/alsa_plugin.c')
| -rw-r--r-- | src/output/alsa_plugin.c | 122 |
1 files changed, 71 insertions, 51 deletions
diff --git a/src/output/alsa_plugin.c b/src/output/alsa_plugin.c index 86c70f19d..d90be7815 100644 --- a/src/output/alsa_plugin.c +++ b/src/output/alsa_plugin.c @@ -218,6 +218,48 @@ byteswap_bitformat(snd_pcm_format_t fmt) } /** + * Attempts to configure the specified sample format. + */ +static int +alsa_output_try_format(snd_pcm_t *pcm, snd_pcm_hw_params_t *hwparams, + struct audio_format *audio_format, + enum sample_format sample_format) +{ + snd_pcm_format_t alsa_format = get_bitformat(sample_format); + if (alsa_format == SND_PCM_FORMAT_UNKNOWN) + return -EINVAL; + + int err = snd_pcm_hw_params_set_format(pcm, hwparams, alsa_format); + if (err == 0) + audio_format->format = sample_format; + + return err; +} + +/** + * Attempts to configure the specified sample format with reversed + * host byte order. + */ +static int +alsa_output_try_reverse(snd_pcm_t *pcm, snd_pcm_hw_params_t *hwparams, + struct audio_format *audio_format, + enum sample_format sample_format) +{ + snd_pcm_format_t alsa_format = + byteswap_bitformat(get_bitformat(sample_format)); + if (alsa_format == SND_PCM_FORMAT_UNKNOWN) + return -EINVAL; + + int err = snd_pcm_hw_params_set_format(pcm, hwparams, alsa_format); + if (err == 0) { + audio_format->format = sample_format; + audio_format->reverse_endian = true; + } + + return err; +} + +/** * Configure a sample format, and probe other formats if that fails. */ static int @@ -234,66 +276,44 @@ alsa_output_setup_format(snd_pcm_t *pcm, snd_pcm_hw_params_t *hwparams, } int err = snd_pcm_hw_params_set_format(pcm, hwparams, bitformat); - if (err == -EINVAL && - byteswap_bitformat(bitformat) != SND_PCM_FORMAT_UNKNOWN) { - err = snd_pcm_hw_params_set_format(pcm, hwparams, - byteswap_bitformat(bitformat)); - if (err == 0) { - g_debug("converting format %s to reverse-endian", - sample_format_to_string(audio_format->format)); - audio_format->reverse_endian = 1; - } - } + if (err != -EINVAL) + return err; - if (err == -EINVAL && (audio_format->format == SAMPLE_FORMAT_S24_P32 || - audio_format->format == SAMPLE_FORMAT_S16)) { - /* fall back to 32 bit, let pcm_convert.c do the conversion */ - err = snd_pcm_hw_params_set_format(pcm, hwparams, - SND_PCM_FORMAT_S32); - if (err == 0) { - g_debug("converting format %s to 32 bit\n", - sample_format_to_string(audio_format->format)); - audio_format->format = SAMPLE_FORMAT_S32; - } - } + err = alsa_output_try_reverse(pcm, hwparams, audio_format, + audio_format->format); + if (err != -EINVAL) + return err; - if (err == -EINVAL && (audio_format->format == SAMPLE_FORMAT_S24_P32 || - audio_format->format == SAMPLE_FORMAT_S16)) { + if (audio_format->format == SAMPLE_FORMAT_S24_P32 || + audio_format->format == SAMPLE_FORMAT_S16) { /* fall back to 32 bit, let pcm_convert.c do the conversion */ - err = snd_pcm_hw_params_set_format(pcm, hwparams, - byteswap_bitformat(SND_PCM_FORMAT_S32)); - if (err == 0) { - g_debug("converting format %s to 32 bit backward-endian\n", - sample_format_to_string(audio_format->format)); - audio_format->format = SAMPLE_FORMAT_S32; - audio_format->reverse_endian = 1; - } - } - if (err == -EINVAL && audio_format->format != SAMPLE_FORMAT_S16) { - /* fall back to 16 bit, let pcm_convert.c do the conversion */ - err = snd_pcm_hw_params_set_format(pcm, hwparams, - SND_PCM_FORMAT_S16); - if (err == 0) { - g_debug("converting format %s to 16 bit\n", - sample_format_to_string(audio_format->format)); - audio_format->format = SAMPLE_FORMAT_S16; - } + err = alsa_output_try_format(pcm, hwparams, audio_format, + SAMPLE_FORMAT_S24_P32); + if (err != -EINVAL) + return err; + + err = alsa_output_try_reverse(pcm, hwparams, audio_format, + SAMPLE_FORMAT_S24_P32); + if (err != -EINVAL) + return err; } - if (err == -EINVAL && audio_format->format != SAMPLE_FORMAT_S16) { + if (audio_format->format != SAMPLE_FORMAT_S16) { /* fall back to 16 bit, let pcm_convert.c do the conversion */ - err = snd_pcm_hw_params_set_format(pcm, hwparams, - byteswap_bitformat(SND_PCM_FORMAT_S16)); - if (err == 0) { - g_debug("converting format %s to 16 bit backward-endian\n", - sample_format_to_string(audio_format->format)); - audio_format->format = SAMPLE_FORMAT_S16; - audio_format->reverse_endian = 1; - } + + err = alsa_output_try_format(pcm, hwparams, audio_format, + SAMPLE_FORMAT_S16); + if (err != -EINVAL) + return err; + + err = alsa_output_try_reverse(pcm, hwparams, audio_format, + SAMPLE_FORMAT_S16); + if (err != -EINVAL) + return err; } - return err; + return -EINVAL; } /** |