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-rw-r--r--sound/core/oss/copy.c92
1 files changed, 92 insertions, 0 deletions
diff --git a/sound/core/oss/copy.c b/sound/core/oss/copy.c
new file mode 100644
index 000000000..05b58d4fc
--- /dev/null
+++ b/sound/core/oss/copy.c
@@ -0,0 +1,92 @@
+/*
+ * Linear conversion Plug-In
+ * Copyright (c) 2000 by Abramo Bagnara <abramo@alsa-project.org>
+ *
+ *
+ * This library is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#include <linux/time.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include "pcm_plugin.h"
+
+static snd_pcm_sframes_t copy_transfer(struct snd_pcm_plugin *plugin,
+ const struct snd_pcm_plugin_channel *src_channels,
+ struct snd_pcm_plugin_channel *dst_channels,
+ snd_pcm_uframes_t frames)
+{
+ unsigned int channel;
+ unsigned int nchannels;
+
+ if (snd_BUG_ON(!plugin || !src_channels || !dst_channels))
+ return -ENXIO;
+ if (frames == 0)
+ return 0;
+ nchannels = plugin->src_format.channels;
+ for (channel = 0; channel < nchannels; channel++) {
+ if (snd_BUG_ON(src_channels->area.first % 8 ||
+ src_channels->area.step % 8))
+ return -ENXIO;
+ if (snd_BUG_ON(dst_channels->area.first % 8 ||
+ dst_channels->area.step % 8))
+ return -ENXIO;
+ if (!src_channels->enabled) {
+ if (dst_channels->wanted)
+ snd_pcm_area_silence(&dst_channels->area, 0, frames, plugin->dst_format.format);
+ dst_channels->enabled = 0;
+ continue;
+ }
+ dst_channels->enabled = 1;
+ snd_pcm_area_copy(&src_channels->area, 0, &dst_channels->area, 0, frames, plugin->src_format.format);
+ src_channels++;
+ dst_channels++;
+ }
+ return frames;
+}
+
+int snd_pcm_plugin_build_copy(struct snd_pcm_substream *plug,
+ struct snd_pcm_plugin_format *src_format,
+ struct snd_pcm_plugin_format *dst_format,
+ struct snd_pcm_plugin **r_plugin)
+{
+ int err;
+ struct snd_pcm_plugin *plugin;
+ int width;
+
+ if (snd_BUG_ON(!r_plugin))
+ return -ENXIO;
+ *r_plugin = NULL;
+
+ if (snd_BUG_ON(src_format->format != dst_format->format))
+ return -ENXIO;
+ if (snd_BUG_ON(src_format->rate != dst_format->rate))
+ return -ENXIO;
+ if (snd_BUG_ON(src_format->channels != dst_format->channels))
+ return -ENXIO;
+
+ width = snd_pcm_format_physical_width(src_format->format);
+ if (snd_BUG_ON(width <= 0))
+ return -ENXIO;
+
+ err = snd_pcm_plugin_build(plug, "copy", src_format, dst_format,
+ 0, &plugin);
+ if (err < 0)
+ return err;
+ plugin->transfer = copy_transfer;
+ *r_plugin = plugin;
+ return 0;
+}