-static int snd_pcm_plug_playback_channels_mask(struct snd_pcm_substream *plug,
- unsigned long *client_vmask)
-{
- struct snd_pcm_plugin *plugin = snd_pcm_plug_last(plug);
- if (plugin == NULL) {
- return 0;
- } else {
- int schannels = plugin->dst_format.channels;
- DECLARE_BITMAP(bs, schannels);
- unsigned long *srcmask;
- unsigned long *dstmask = bs;
- int err;
- bitmap_fill(dstmask, schannels);
-
- while (1) {
- err = plugin->src_channels_mask(plugin, dstmask, &srcmask);
- if (err < 0)
- return err;
- dstmask = srcmask;
- if (plugin->prev == NULL)
- break;
- plugin = plugin->prev;
- }
- bitmap_and(client_vmask, client_vmask, dstmask, plugin->src_format.channels);
- return 0;
- }
-}
-
-static int snd_pcm_plug_playback_disable_useless_channels(struct snd_pcm_substream *plug,
- struct snd_pcm_plugin_channel *src_channels)
-{
- struct snd_pcm_plugin *plugin = snd_pcm_plug_first(plug);
- unsigned int nchannels = plugin->src_format.channels;
- DECLARE_BITMAP(bs, nchannels);
- unsigned long *srcmask = bs;
- int err;
- unsigned int channel;
- for (channel = 0; channel < nchannels; channel++) {
- if (src_channels[channel].enabled)
- set_bit(channel, srcmask);
- else
- clear_bit(channel, srcmask);
- }
- err = snd_pcm_plug_playback_channels_mask(plug, srcmask);
- if (err < 0)
- return err;
- for (channel = 0; channel < nchannels; channel++) {
- if (!test_bit(channel, srcmask))
- src_channels[channel].enabled = 0;
- }
- return 0;
-}
-
-static int snd_pcm_plug_capture_disable_useless_channels(struct snd_pcm_substream *plug,
- struct snd_pcm_plugin_channel *src_channels,
- struct snd_pcm_plugin_channel *client_channels)
-{
- struct snd_pcm_plugin *plugin = snd_pcm_plug_last(plug);
- unsigned int nchannels = plugin->dst_format.channels;
- DECLARE_BITMAP(bs, nchannels);
- unsigned long *dstmask = bs;
- unsigned long *srcmask;
- int err;
- unsigned int channel;
- for (channel = 0; channel < nchannels; channel++) {
- if (client_channels[channel].enabled)
- set_bit(channel, dstmask);
- else
- clear_bit(channel, dstmask);
- }
- while (plugin) {
- err = plugin->src_channels_mask(plugin, dstmask, &srcmask);
- if (err < 0)
- return err;
- dstmask = srcmask;
- plugin = plugin->prev;
- }
- plugin = snd_pcm_plug_first(plug);
- nchannels = plugin->src_format.channels;
- for (channel = 0; channel < nchannels; channel++) {
- if (!test_bit(channel, dstmask))
- src_channels[channel].enabled = 0;
- }
- return 0;
-}
-