X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=sound%2Fcore%2Foss%2Fmulaw.c;h=77f96194a0eda5eff6ed2cb3e66ae32d5207f88f;hb=c44df7413fd711bca818111b94cbd7ce5f3600a9;hp=2eb18807e6d04662f9d85bed3355d8ad2cd5b5e6;hpb=95d465fd750897ab32462a6702fbfe1b122cbbc0;p=linux-2.6

diff --git a/sound/core/oss/mulaw.c b/sound/core/oss/mulaw.c
index 2eb18807e6..77f96194a0 100644
--- a/sound/core/oss/mulaw.c
+++ b/sound/core/oss/mulaw.c
@@ -1,6 +1,6 @@
 /*
  *  Mu-Law conversion Plug-In Interface
- *  Copyright (c) 1999 by Jaroslav Kysela <perex@suse.cz>
+ *  Copyright (c) 1999 by Jaroslav Kysela <perex@perex.cz>
  *                        Uros Bizjak <uros@kss-loka.si>
  *
  *  Based on reference implementation by Sun Microsystems, Inc.
@@ -21,10 +21,6 @@
  *
  */
   
-#include <sound/driver.h>
-
-#ifdef CONFIG_SND_PCM_OSS_PLUGINS
-
 #include <linux/time.h>
 #include <sound/core.h>
 #include <sound/pcm.h>
@@ -149,19 +145,32 @@ typedef void (*mulaw_f)(struct snd_pcm_plugin *plugin,
 
 struct mulaw_priv {
 	mulaw_f func;
-	int conv;
+	int cvt_endian;			/* need endian conversion? */
+	unsigned int native_ofs;	/* byte offset in native format */
+	unsigned int copy_ofs;		/* byte offset in s16 format */
+	unsigned int native_bytes;	/* byte size of the native format */
+	unsigned int copy_bytes;	/* bytes to copy per conversion */
+	u16 flip; /* MSB flip for signedness, done after endian conversion */
 };
 
+static inline void cvt_s16_to_native(struct mulaw_priv *data,
+				     unsigned char *dst, u16 sample)
+{
+	sample ^= data->flip;
+	if (data->cvt_endian)
+		sample = swab16(sample);
+	if (data->native_bytes > data->copy_bytes)
+		memset(dst, 0, data->native_bytes);
+	memcpy(dst + data->native_ofs, (char *)&sample + data->copy_ofs,
+	       data->copy_bytes);
+}
+
 static void mulaw_decode(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)
 {
-#define PUT_S16_LABELS
-#include "plugin_ops.h"
-#undef PUT_S16_LABELS
 	struct mulaw_priv *data = (struct mulaw_priv *)plugin->extra_data;
-	void *put = put_s16_labels[data->conv];
 	int channel;
 	int nchannels = plugin->src_format.channels;
 	for (channel = 0; channel < nchannels; ++channel) {
@@ -183,30 +192,33 @@ static void mulaw_decode(struct snd_pcm_plugin *plugin,
 		frames1 = frames;
 		while (frames1-- > 0) {
 			signed short sample = ulaw2linear(*src);
-			goto *put;
-#define PUT_S16_END after
-#include "plugin_ops.h"
-#undef PUT_S16_END
-		after:
+			cvt_s16_to_native(data, dst, sample);
 			src += src_step;
 			dst += dst_step;
 		}
 	}
 }
 
+static inline signed short cvt_native_to_s16(struct mulaw_priv *data,
+					     unsigned char *src)
+{
+	u16 sample = 0;
+	memcpy((char *)&sample + data->copy_ofs, src + data->native_ofs,
+	       data->copy_bytes);
+	if (data->cvt_endian)
+		sample = swab16(sample);
+	sample ^= data->flip;
+	return (signed short)sample;
+}
+
 static void mulaw_encode(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)
 {
-#define GET_S16_LABELS
-#include "plugin_ops.h"
-#undef GET_S16_LABELS
 	struct mulaw_priv *data = (struct mulaw_priv *)plugin->extra_data;
-	void *get = get_s16_labels[data->conv];
 	int channel;
 	int nchannels = plugin->src_format.channels;
-	signed short sample = 0;
 	for (channel = 0; channel < nchannels; ++channel) {
 		char *src;
 		char *dst;
@@ -225,11 +237,7 @@ static void mulaw_encode(struct snd_pcm_plugin *plugin,
 		dst_step = dst_channels[channel].area.step / 8;
 		frames1 = frames;
 		while (frames1-- > 0) {
-			goto *get;
-#define GET_S16_END after
-#include "plugin_ops.h"
-#undef GET_S16_END
-		after:
+			signed short sample = cvt_native_to_s16(data, src);
 			*dst = linear2ulaw(sample);
 			src += src_step;
 			dst += dst_step;
@@ -265,23 +273,25 @@ static snd_pcm_sframes_t mulaw_transfer(struct snd_pcm_plugin *plugin,
 	return frames;
 }
 
-static int getput_index(int format)
+static void init_data(struct mulaw_priv *data, int format)
 {
-	int sign, width, endian;
-	sign = !snd_pcm_format_signed(format);
-	width = snd_pcm_format_width(format) / 8 - 1;
-	if (width < 0 || width > 3) {
-		snd_printk(KERN_ERR "snd-pcm-oss: invalid format %d\n", format);
-		width = 0;
-	}
 #ifdef SNDRV_LITTLE_ENDIAN
-	endian = snd_pcm_format_big_endian(format);
+	data->cvt_endian = snd_pcm_format_big_endian(format) > 0;
 #else
-	endian = snd_pcm_format_little_endian(format);
+	data->cvt_endian = snd_pcm_format_little_endian(format) > 0;
 #endif
-	if (endian < 0)
-		endian = 0;
-	return width * 4 + endian * 2 + sign;
+	if (!snd_pcm_format_signed(format))
+		data->flip = 0x8000;
+	data->native_bytes = snd_pcm_format_physical_width(format) / 8;
+	data->copy_bytes = data->native_bytes < 2 ? 1 : 2;
+	if (snd_pcm_format_little_endian(format)) {
+		data->native_ofs = data->native_bytes - data->copy_bytes;
+		data->copy_ofs = 2 - data->copy_bytes;
+	} else {
+		/* S24 in 4bytes need an 1 byte offset */
+		data->native_ofs = data->native_bytes -
+			snd_pcm_format_width(format) / 8;
+	}
 }
 
 int snd_pcm_plugin_build_mulaw(struct snd_pcm_substream *plug,
@@ -322,11 +332,8 @@ int snd_pcm_plugin_build_mulaw(struct snd_pcm_substream *plug,
 		return err;
 	data = (struct mulaw_priv *)plugin->extra_data;
 	data->func = func;
-	data->conv = getput_index(format->format);
-	snd_assert(data->conv >= 0 && data->conv < 4*2*2, return -EINVAL);
+	init_data(data, format->format);
 	plugin->transfer = mulaw_transfer;
 	*r_plugin = plugin;
 	return 0;
 }
-
-#endif