From 64d27f96cb719cf8b5dae634c4c548049d4ae6bf Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai@suse.de>
Date: Wed, 8 Aug 2007 16:49:08 +0200
Subject: [PATCH] [ALSA] Support 3-bytes 24bit format in PCM OSS emulation

Add the support of 3-bytes 24bit formats in PCM OSS emulation.
Also removed snd_pcm_build_linear_format() function.  It's exported
just for OSS emulation, and now the code was changed without calling
this function.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
---
 sound/core/oss/pcm_plugin.c | 56 +++++++++++++++++++------------------
 sound/core/pcm_misc.c       | 32 ---------------------
 2 files changed, 29 insertions(+), 59 deletions(-)

diff --git a/sound/core/oss/pcm_plugin.c b/sound/core/oss/pcm_plugin.c
index c0afb92869d3..25dcf96a5dc6 100644
--- a/sound/core/oss/pcm_plugin.c
+++ b/sound/core/oss/pcm_plugin.c
@@ -264,6 +264,8 @@ static int snd_pcm_plug_formats(struct snd_mask *mask, int format)
 		       SNDRV_PCM_FMTBIT_U16_BE | SNDRV_PCM_FMTBIT_S16_BE |
 		       SNDRV_PCM_FMTBIT_U24_LE | SNDRV_PCM_FMTBIT_S24_LE |
 		       SNDRV_PCM_FMTBIT_U24_BE | SNDRV_PCM_FMTBIT_S24_BE |
+		       SNDRV_PCM_FMTBIT_U24_3LE | SNDRV_PCM_FMTBIT_S24_3LE |
+		       SNDRV_PCM_FMTBIT_U24_3BE | SNDRV_PCM_FMTBIT_S24_3BE |
 		       SNDRV_PCM_FMTBIT_U32_LE | SNDRV_PCM_FMTBIT_S32_LE |
 		       SNDRV_PCM_FMTBIT_U32_BE | SNDRV_PCM_FMTBIT_S32_BE);
 	snd_mask_set(&formats, SNDRV_PCM_FORMAT_MU_LAW);
@@ -280,6 +282,10 @@ static int preferred_formats[] = {
 	SNDRV_PCM_FORMAT_S16_BE,
 	SNDRV_PCM_FORMAT_U16_LE,
 	SNDRV_PCM_FORMAT_U16_BE,
+	SNDRV_PCM_FORMAT_S24_3LE,
+	SNDRV_PCM_FORMAT_S24_3BE,
+	SNDRV_PCM_FORMAT_U24_3LE,
+	SNDRV_PCM_FORMAT_U24_3BE,
 	SNDRV_PCM_FORMAT_S24_LE,
 	SNDRV_PCM_FORMAT_S24_BE,
 	SNDRV_PCM_FORMAT_U24_LE,
@@ -294,41 +300,37 @@ static int preferred_formats[] = {
 
 int snd_pcm_plug_slave_format(int format, struct snd_mask *format_mask)
 {
+	int i;
+
 	if (snd_mask_test(format_mask, format))
 		return format;
 	if (! snd_pcm_plug_formats(format_mask, format))
 		return -EINVAL;
 	if (snd_pcm_format_linear(format)) {
-		int width = snd_pcm_format_width(format);
-		int unsignd = snd_pcm_format_unsigned(format);
-		int big = snd_pcm_format_big_endian(format);
-		int format1;
-		int wid, width1=width;
-		int dwidth1 = 8;
-		for (wid = 0; wid < 4; ++wid) {
-			int end, big1 = big;
-			for (end = 0; end < 2; ++end) {
-				int sgn, unsignd1 = unsignd;
-				for (sgn = 0; sgn < 2; ++sgn) {
-					format1 = snd_pcm_build_linear_format(width1, unsignd1, big1);
-					if (format1 >= 0 &&
-					    snd_mask_test(format_mask, format1))
-						goto _found;
-					unsignd1 = !unsignd1;
-				}
-				big1 = !big1;
-			}
-			if (width1 == 32) {
-				dwidth1 = -dwidth1;
-				width1 = width;
+		unsigned int width = snd_pcm_format_width(format);
+		int unsignd = snd_pcm_format_unsigned(format) > 0;
+		int big = snd_pcm_format_big_endian(format) > 0;
+		unsigned int badness, best = -1;
+		int best_format = -1;
+		for (i = 0; i < ARRAY_SIZE(preferred_formats); i++) {
+			int f = preferred_formats[i];
+			unsigned int w;
+			if (!snd_mask_test(format_mask, f))
+				continue;
+			w = snd_pcm_format_width(f);
+			if (w >= width)
+				badness = w - width;
+			else
+				badness = width - w + 32;
+			badness += snd_pcm_format_unsigned(f) != unsignd;
+			badness += snd_pcm_format_big_endian(f) != big;
+			if (badness < best) {
+				best_format = f;
+				best = badness;
 			}
-			width1 += dwidth1;
 		}
-		return -EINVAL;
-	_found:
-		return format1;
+		return best_format >= 0 ? best_format : -EINVAL;
 	} else {
-		unsigned int i;
 		switch (format) {
 		case SNDRV_PCM_FORMAT_MU_LAW:
 			for (i = 0; i < ARRAY_SIZE(preferred_formats); ++i) {
diff --git a/sound/core/pcm_misc.c b/sound/core/pcm_misc.c
index 0019c59a779d..9142fce4dda2 100644
--- a/sound/core/pcm_misc.c
+++ b/sound/core/pcm_misc.c
@@ -422,38 +422,6 @@ int snd_pcm_format_set_silence(snd_pcm_format_t format, void *data, unsigned int
 
 EXPORT_SYMBOL(snd_pcm_format_set_silence);
 
-/* [width][unsigned][bigendian] */
-static int linear_formats[4][2][2] = {
-	{{ SNDRV_PCM_FORMAT_S8, SNDRV_PCM_FORMAT_S8},
-	 { SNDRV_PCM_FORMAT_U8, SNDRV_PCM_FORMAT_U8}},
-	{{SNDRV_PCM_FORMAT_S16_LE, SNDRV_PCM_FORMAT_S16_BE},
-	 {SNDRV_PCM_FORMAT_U16_LE, SNDRV_PCM_FORMAT_U16_BE}},
-	{{SNDRV_PCM_FORMAT_S24_LE, SNDRV_PCM_FORMAT_S24_BE},
-	 {SNDRV_PCM_FORMAT_U24_LE, SNDRV_PCM_FORMAT_U24_BE}},
-	{{SNDRV_PCM_FORMAT_S32_LE, SNDRV_PCM_FORMAT_S32_BE},
-	 {SNDRV_PCM_FORMAT_U32_LE, SNDRV_PCM_FORMAT_U32_BE}}
-};
-
-/**
- * snd_pcm_build_linear_format - return the suitable linear format for the given condition
- * @width: the bit-width
- * @unsignd: 1 if unsigned, 0 if signed.
- * @big_endian: 1 if big-endian, 0 if little-endian
- *
- * Returns the suitable linear format for the given condition.
- */
-snd_pcm_format_t snd_pcm_build_linear_format(int width, int unsignd, int big_endian)
-{
-	if (width & 7)
-		return SND_PCM_FORMAT_UNKNOWN;
-	width = (width / 8) - 1;
-	if (width < 0 || width >= 4)
-		return SND_PCM_FORMAT_UNKNOWN;
-	return linear_formats[width][!!unsignd][!!big_endian];
-}
-
-EXPORT_SYMBOL(snd_pcm_build_linear_format);
-
 /**
  * snd_pcm_limit_hw_rates - determine rate_min/rate_max fields
  * @runtime: the runtime instance
-- 
2.20.1