1 files changed, 470 insertions, 0 deletions
diff --git a/sound/core/pcm_misc.c b/sound/core/pcm_misc.c
new file mode 100644
index 0000000..ea2bf82
--- /dev/null
+++ b/sound/core/pcm_misc.c
@@ -0,0 +1,470 @@
+/*
+ *  PCM Interface - misc routines
+ *  Copyright (c) 1998 by Jaroslav Kysela <perex@perex.cz>
+ *
+ *
+ *   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>
+#define SND_PCM_FORMAT_UNKNOWN (-1)
+
+/* NOTE: "signed" prefix must be given below since the default char is
+ *       unsigned on some architectures!
+ */
+struct pcm_format_data {
+	unsigned char width;	/* bit width */
+	unsigned char phys;	/* physical bit width */
+	signed char le;	/* 0 = big-endian, 1 = little-endian, -1 = others */
+	signed char signd;	/* 0 = unsigned, 1 = signed, -1 = others */
+	unsigned char silence[8];	/* silence data to fill */
+};
+
+static struct pcm_format_data pcm_formats[SNDRV_PCM_FORMAT_LAST+1] = {
+	[SNDRV_PCM_FORMAT_S8] = {
+		.width = 8, .phys = 8, .le = -1, .signd = 1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_U8] = {
+		.width = 8, .phys = 8, .le = -1, .signd = 0,
+		.silence = { 0x80 },
+	},
+	[SNDRV_PCM_FORMAT_S16_LE] = {
+		.width = 16, .phys = 16, .le = 1, .signd = 1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_S16_BE] = {
+		.width = 16, .phys = 16, .le = 0, .signd = 1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_U16_LE] = {
+		.width = 16, .phys = 16, .le = 1, .signd = 0,
+		.silence = { 0x00, 0x80 },
+	},
+	[SNDRV_PCM_FORMAT_U16_BE] = {
+		.width = 16, .phys = 16, .le = 0, .signd = 0,
+		.silence = { 0x80, 0x00 },
+	},
+	[SNDRV_PCM_FORMAT_S24_LE] = {
+		.width = 24, .phys = 32, .le = 1, .signd = 1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_S24_BE] = {
+		.width = 24, .phys = 32, .le = 0, .signd = 1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_U24_LE] = {
+		.width = 24, .phys = 32, .le = 1, .signd = 0,
+		.silence = { 0x00, 0x00, 0x80 },
+	},
+	[SNDRV_PCM_FORMAT_U24_BE] = {
+		.width = 24, .phys = 32, .le = 0, .signd = 0,
+		.silence = { 0x00, 0x80, 0x00, 0x00 },
+	},
+	[SNDRV_PCM_FORMAT_S32_LE] = {
+		.width = 32, .phys = 32, .le = 1, .signd = 1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_S32_BE] = {
+		.width = 32, .phys = 32, .le = 0, .signd = 1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_U32_LE] = {
+		.width = 32, .phys = 32, .le = 1, .signd = 0,
+		.silence = { 0x00, 0x00, 0x00, 0x80 },
+	},
+	[SNDRV_PCM_FORMAT_U32_BE] = {
+		.width = 32, .phys = 32, .le = 0, .signd = 0,
+		.silence = { 0x80, 0x00, 0x00, 0x00 },
+	},
+	[SNDRV_PCM_FORMAT_FLOAT_LE] = {
+		.width = 32, .phys = 32, .le = 1, .signd = -1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_FLOAT_BE] = {
+		.width = 32, .phys = 32, .le = 0, .signd = -1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_FLOAT64_LE] = {
+		.width = 64, .phys = 64, .le = 1, .signd = -1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_FLOAT64_BE] = {
+		.width = 64, .phys = 64, .le = 0, .signd = -1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE] = {
+		.width = 32, .phys = 32, .le = 1, .signd = -1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE] = {
+		.width = 32, .phys = 32, .le = 0, .signd = -1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_MU_LAW] = {
+		.width = 8, .phys = 8, .le = -1, .signd = -1,
+		.silence = { 0x7f },
+	},
+	[SNDRV_PCM_FORMAT_A_LAW] = {
+		.width = 8, .phys = 8, .le = -1, .signd = -1,
+		.silence = { 0x55 },
+	},
+	[SNDRV_PCM_FORMAT_IMA_ADPCM] = {
+		.width = 4, .phys = 4, .le = -1, .signd = -1,
+		.silence = {},
+	},
+	/* FIXME: the following three formats are not defined properly yet */
+	[SNDRV_PCM_FORMAT_MPEG] = {
+		.le = -1, .signd = -1,
+	},
+	[SNDRV_PCM_FORMAT_GSM] = {
+		.le = -1, .signd = -1,
+	},
+	[SNDRV_PCM_FORMAT_SPECIAL] = {
+		.le = -1, .signd = -1,
+	},
+	[SNDRV_PCM_FORMAT_S24_3LE] = {
+		.width = 24, .phys = 24, .le = 1, .signd = 1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_S24_3BE] = {
+		.width = 24, .phys = 24, .le = 0, .signd = 1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_U24_3LE] = {
+		.width = 24, .phys = 24, .le = 1, .signd = 0,
+		.silence = { 0x00, 0x00, 0x80 },
+	},
+	[SNDRV_PCM_FORMAT_U24_3BE] = {
+		.width = 24, .phys = 24, .le = 0, .signd = 0,
+		.silence = { 0x80, 0x00, 0x00 },
+	},
+	[SNDRV_PCM_FORMAT_S20_3LE] = {
+		.width = 20, .phys = 24, .le = 1, .signd = 1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_S20_3BE] = {
+		.width = 20, .phys = 24, .le = 0, .signd = 1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_U20_3LE] = {
+		.width = 20, .phys = 24, .le = 1, .signd = 0,
+		.silence = { 0x00, 0x00, 0x08 },
+	},
+	[SNDRV_PCM_FORMAT_U20_3BE] = {
+		.width = 20, .phys = 24, .le = 0, .signd = 0,
+		.silence = { 0x08, 0x00, 0x00 },
+	},
+	[SNDRV_PCM_FORMAT_S18_3LE] = {
+		.width = 18, .phys = 24, .le = 1, .signd = 1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_S18_3BE] = {
+		.width = 18, .phys = 24, .le = 0, .signd = 1,
+		.silence = {},
+	},
+	[SNDRV_PCM_FORMAT_U18_3LE] = {
+		.width = 18, .phys = 24, .le = 1, .signd = 0,
+		.silence = { 0x00, 0x00, 0x02 },
+	},
+	[SNDRV_PCM_FORMAT_U18_3BE] = {
+		.width = 18, .phys = 24, .le = 0, .signd = 0,
+		.silence = { 0x02, 0x00, 0x00 },
+	},
+};
+
+
+/**
+ * snd_pcm_format_signed - Check the PCM format is signed linear
+ * @format: the format to check
+ *
+ * Returns 1 if the given PCM format is signed linear, 0 if unsigned
+ * linear, and a negative error code for non-linear formats.
+ */
+int snd_pcm_format_signed(snd_pcm_format_t format)
+{
+	int val;
+	if (format < 0 || format > SNDRV_PCM_FORMAT_LAST)
+		return -EINVAL;
+	if ((val = pcm_formats[format].signd) < 0)
+		return -EINVAL;
+	return val;
+}
+
+EXPORT_SYMBOL(snd_pcm_format_signed);
+
+/**
+ * snd_pcm_format_unsigned - Check the PCM format is unsigned linear
+ * @format: the format to check
+ *
+ * Returns 1 if the given PCM format is unsigned linear, 0 if signed
+ * linear, and a negative error code for non-linear formats.
+ */
+int snd_pcm_format_unsigned(snd_pcm_format_t format)
+{
+	int val;
+
+	val = snd_pcm_format_signed(format);
+	if (val < 0)
+		return val;
+	return !val;
+}
+
+EXPORT_SYMBOL(snd_pcm_format_unsigned);
+
+/**
+ * snd_pcm_format_linear - Check the PCM format is linear
+ * @format: the format to check
+ *
+ * Returns 1 if the given PCM format is linear, 0 if not.
+ */
+int snd_pcm_format_linear(snd_pcm_format_t format)
+{
+	return snd_pcm_format_signed(format) >= 0;
+}
+
+EXPORT_SYMBOL(snd_pcm_format_linear);
+
+/**
+ * snd_pcm_format_little_endian - Check the PCM format is little-endian
+ * @format: the format to check
+ *
+ * Returns 1 if the given PCM format is little-endian, 0 if
+ * big-endian, or a negative error code if endian not specified.
+ */
+int snd_pcm_format_little_endian(snd_pcm_format_t format)
+{
+	int val;
+	if (format < 0 || format > SNDRV_PCM_FORMAT_LAST)
+		return -EINVAL;
+	if ((val = pcm_formats[format].le) < 0)
+		return -EINVAL;
+	return val;
+}
+
+EXPORT_SYMBOL(snd_pcm_format_little_endian);
+
+/**
+ * snd_pcm_format_big_endian - Check the PCM format is big-endian
+ * @format: the format to check
+ *
+ * Returns 1 if the given PCM format is big-endian, 0 if
+ * little-endian, or a negative error code if endian not specified.
+ */
+int snd_pcm_format_big_endian(snd_pcm_format_t format)
+{
+	int val;
+
+	val = snd_pcm_format_little_endian(format);
+	if (val < 0)
+		return val;
+	return !val;
+}
+
+EXPORT_SYMBOL(snd_pcm_format_big_endian);
+
+/**
+ * snd_pcm_format_width - return the bit-width of the format
+ * @format: the format to check
+ *
+ * Returns the bit-width of the format, or a negative error code
+ * if unknown format.
+ */
+int snd_pcm_format_width(snd_pcm_format_t format)
+{
+	int val;
+	if (format < 0 || format > SNDRV_PCM_FORMAT_LAST)
+		return -EINVAL;
+	if ((val = pcm_formats[format].width) == 0)
+		return -EINVAL;
+	return val;
+}
+
+EXPORT_SYMBOL(snd_pcm_format_width);
+
+/**
+ * snd_pcm_format_physical_width - return the physical bit-width of the format
+ * @format: the format to check
+ *
+ * Returns the physical bit-width of the format, or a negative error code
+ * if unknown format.
+ */
+int snd_pcm_format_physical_width(snd_pcm_format_t format)
+{
+	int val;
+	if (format < 0 || format > SNDRV_PCM_FORMAT_LAST)
+		return -EINVAL;
+	if ((val = pcm_formats[format].phys) == 0)
+		return -EINVAL;
+	return val;
+}
+
+EXPORT_SYMBOL(snd_pcm_format_physical_width);
+
+/**
+ * snd_pcm_format_size - return the byte size of samples on the given format
+ * @format: the format to check
+ * @samples: sampling rate
+ *
+ * Returns the byte size of the given samples for the format, or a
+ * negative error code if unknown format.
+ */
+ssize_t snd_pcm_format_size(snd_pcm_format_t format, size_t samples)
+{
+	int phys_width = snd_pcm_format_physical_width(format);
+	if (phys_width < 0)
+		return -EINVAL;
+	return samples * phys_width / 8;
+}
+
+EXPORT_SYMBOL(snd_pcm_format_size);
+
+/**
+ * snd_pcm_format_silence_64 - return the silent data in 8 bytes array
+ * @format: the format to check
+ *
+ * Returns the format pattern to fill or NULL if error.
+ */
+const unsigned char *snd_pcm_format_silence_64(snd_pcm_format_t format)
+{
+	if (format < 0 || format > SNDRV_PCM_FORMAT_LAST)
+		return NULL;
+	if (! pcm_formats[format].phys)
+		return NULL;
+	return pcm_formats[format].silence;
+}
+
+EXPORT_SYMBOL(snd_pcm_format_silence_64);
+
+/**
+ * snd_pcm_format_set_silence - set the silence data on the buffer
+ * @format: the PCM format
+ * @data: the buffer pointer
+ * @samples: the number of samples to set silence
+ *
+ * Sets the silence data on the buffer for the given samples.
+ *
+ * Returns zero if successful, or a negative error code on failure.
+ */
+int snd_pcm_format_set_silence(snd_pcm_format_t format, void *data, unsigned int samples)
+{
+	int width;
+	unsigned char *dst, *pat;
+
+	if (format < 0 || format > SNDRV_PCM_FORMAT_LAST)
+		return -EINVAL;
+	if (samples == 0)
+		return 0;
+	width = pcm_formats[format].phys; /* physical width */
+	pat = pcm_formats[format].silence;
+	if (! width)
+		return -EINVAL;
+	/* signed or 1 byte data */
+	if (pcm_formats[format].signd == 1 || width <= 8) {
+		unsigned int bytes = samples * width / 8;
+		memset(data, *pat, bytes);
+		return 0;
+	}
+	/* non-zero samples, fill using a loop */
+	width /= 8;
+	dst = data;
+#if 0
+	while (samples--) {
+		memcpy(dst, pat, width);
+		dst += width;
+	}
+#else
+	/* a bit optimization for constant width */
+	switch (width) {
+	case 2:
+		while (samples--) {
+			memcpy(dst, pat, 2);
+			dst += 2;
+		}
+		break;
+	case 3:
+		while (samples--) {
+			memcpy(dst, pat, 3);
+			dst += 3;
+		}
+		break;
+	case 4:
+		while (samples--) {
+			memcpy(dst, pat, 4);
+			dst += 4;
+		}
+		break;
+	case 8:
+		while (samples--) {
+			memcpy(dst, pat, 8);
+			dst += 8;
+		}
+		break;
+	}
+#endif
+	return 0;
+}
+
+EXPORT_SYMBOL(snd_pcm_format_set_silence);
+
+/**
+ * snd_pcm_limit_hw_rates - determine rate_min/rate_max fields
+ * @runtime: the runtime instance
+ *
+ * Determines the rate_min and rate_max fields from the rates bits of
+ * the given runtime->hw.
+ *
+ * Returns zero if successful.
+ */
+int snd_pcm_limit_hw_rates(struct snd_pcm_runtime *runtime)
+{
+	int i;
+	for (i = 0; i < (int)snd_pcm_known_rates.count; i++) {
+		if (runtime->hw.rates & (1 << i)) {
+			runtime->hw.rate_min = snd_pcm_known_rates.list[i];
+			break;
+		}
+	}
+	for (i = (int)snd_pcm_known_rates.count - 1; i >= 0; i--) {
+		if (runtime->hw.rates & (1 << i)) {
+			runtime->hw.rate_max = snd_pcm_known_rates.list[i];
+			break;
+		}
+	}
+	return 0;
+}
+
+EXPORT_SYMBOL(snd_pcm_limit_hw_rates);
+
+/**
+ * snd_pcm_rate_to_rate_bit - converts sample rate to SNDRV_PCM_RATE_xxx bit
+ * @rate: the sample rate to convert
+ *
+ * Returns the SNDRV_PCM_RATE_xxx flag that corresponds to the given rate, or
+ * SNDRV_PCM_RATE_KNOT for an unknown rate.
+ */
+unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate)
+{
+	unsigned int i;
+
+	for (i = 0; i < snd_pcm_known_rates.count; i++)
+		if (snd_pcm_known_rates.list[i] == rate)
+			return 1u << i;
+	return SNDRV_PCM_RATE_KNOT;
+}
+EXPORT_SYMBOL(snd_pcm_rate_to_rate_bit);