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  • Committer: Bazaar Package Importer
  • Author(s): Amit Kucheria, Amit Kucheria
  • Date: 2010-03-10 02:28:15 UTC
  • Revision ID: james.westby@ubuntu.com-20100310022815-7sd3gwvn5kenaq33
Tags: 2.6.33-500.1
[ Amit Kucheria ]

* Initial release of a 2.6.33-based OMAP kernel
* UBUNTU: [Upstream] Fix omap 1-wire driver compilation
* UBUNTU: ubuntu: AppArmor -- update to mainline 2010-03-04

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sound/core/oss/linear.c
 
1
/*
 
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 *  Linear conversion Plug-In
 
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 *  Copyright (c) 1999 by Jaroslav Kysela <perex@perex.cz>,
 
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 *                        Abramo Bagnara <abramo@alsa-project.org>
 
5
 *
 
6
 *
 
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 *   This library is free software; you can redistribute it and/or modify
 
8
 *   it under the terms of the GNU Library General Public License as
 
9
 *   published by the Free Software Foundation; either version 2 of
 
10
 *   the License, or (at your option) any later version.
 
11
 *
 
12
 *   This program is distributed in the hope that it will be useful,
 
13
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 
14
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 
15
 *   GNU Library General Public License for more details.
 
16
 *
 
17
 *   You should have received a copy of the GNU Library General Public
 
18
 *   License along with this library; if not, write to the Free Software
 
19
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 
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 *
 
21
 */
 
22
 
 
23
#include <linux/time.h>
 
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#include <sound/core.h>
 
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#include <sound/pcm.h>
 
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#include "pcm_plugin.h"
 
27
 
 
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/*
 
29
 *  Basic linear conversion plugin
 
30
 */
 
31
 
 
32
struct linear_priv {
 
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        int cvt_endian;         /* need endian conversion? */
 
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        unsigned int src_ofs;   /* byte offset in source format */
 
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        unsigned int dst_ofs;   /* byte soffset in destination format */
 
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        unsigned int copy_ofs;  /* byte offset in temporary u32 data */
 
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        unsigned int dst_bytes;         /* byte size of destination format */
 
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        unsigned int copy_bytes;        /* bytes to copy per conversion */
 
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        unsigned int flip; /* MSB flip for signeness, done after endian conv */
 
40
};
 
41
 
 
42
static inline void do_convert(struct linear_priv *data,
 
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                              unsigned char *dst, unsigned char *src)
 
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{
 
45
        unsigned int tmp = 0;
 
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        unsigned char *p = (unsigned char *)&tmp;
 
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        memcpy(p + data->copy_ofs, src + data->src_ofs, data->copy_bytes);
 
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        if (data->cvt_endian)
 
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                tmp = swab32(tmp);
 
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        tmp ^= data->flip;
 
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        memcpy(dst, p + data->dst_ofs, data->dst_bytes);
 
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}
 
54
 
 
55
static void convert(struct snd_pcm_plugin *plugin,
 
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                    const struct snd_pcm_plugin_channel *src_channels,
 
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                    struct snd_pcm_plugin_channel *dst_channels,
 
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                    snd_pcm_uframes_t frames)
 
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{
 
60
        struct linear_priv *data = (struct linear_priv *)plugin->extra_data;
 
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        int channel;
 
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        int nchannels = plugin->src_format.channels;
 
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        for (channel = 0; channel < nchannels; ++channel) {
 
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                char *src;
 
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                char *dst;
 
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                int src_step, dst_step;
 
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                snd_pcm_uframes_t frames1;
 
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                if (!src_channels[channel].enabled) {
 
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                        if (dst_channels[channel].wanted)
 
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                                snd_pcm_area_silence(&dst_channels[channel].area, 0, frames, plugin->dst_format.format);
 
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                        dst_channels[channel].enabled = 0;
 
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                        continue;
 
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                }
 
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                dst_channels[channel].enabled = 1;
 
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                src = src_channels[channel].area.addr + src_channels[channel].area.first / 8;
 
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                dst = dst_channels[channel].area.addr + dst_channels[channel].area.first / 8;
 
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                src_step = src_channels[channel].area.step / 8;
 
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                dst_step = dst_channels[channel].area.step / 8;
 
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                frames1 = frames;
 
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                while (frames1-- > 0) {
 
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                        do_convert(data, dst, src);
 
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                        src += src_step;
 
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                        dst += dst_step;
 
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                }
 
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        }
 
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}
 
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static snd_pcm_sframes_t linear_transfer(struct snd_pcm_plugin *plugin,
 
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                               const struct snd_pcm_plugin_channel *src_channels,
 
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                               struct snd_pcm_plugin_channel *dst_channels,
 
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                               snd_pcm_uframes_t frames)
 
92
{
 
93
        struct linear_priv *data;
 
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        if (snd_BUG_ON(!plugin || !src_channels || !dst_channels))
 
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                return -ENXIO;
 
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        data = (struct linear_priv *)plugin->extra_data;
 
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        if (frames == 0)
 
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                return 0;
 
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#ifdef CONFIG_SND_DEBUG
 
101
        {
 
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                unsigned int channel;
 
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                for (channel = 0; channel < plugin->src_format.channels; channel++) {
 
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                        if (snd_BUG_ON(src_channels[channel].area.first % 8 ||
 
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                                       src_channels[channel].area.step % 8))
 
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                                return -ENXIO;
 
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                        if (snd_BUG_ON(dst_channels[channel].area.first % 8 ||
 
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                                       dst_channels[channel].area.step % 8))
 
109
                                return -ENXIO;
 
110
                }
 
111
        }
 
112
#endif
 
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        convert(plugin, src_channels, dst_channels, frames);
 
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        return frames;
 
115
}
 
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117
static void init_data(struct linear_priv *data, int src_format, int dst_format)
 
118
{
 
119
        int src_le, dst_le, src_bytes, dst_bytes;
 
120
 
 
121
        src_bytes = snd_pcm_format_width(src_format) / 8;
 
122
        dst_bytes = snd_pcm_format_width(dst_format) / 8;
 
123
        src_le = snd_pcm_format_little_endian(src_format) > 0;
 
124
        dst_le = snd_pcm_format_little_endian(dst_format) > 0;
 
125
 
 
126
        data->dst_bytes = dst_bytes;
 
127
        data->cvt_endian = src_le != dst_le;
 
128
        data->copy_bytes = src_bytes < dst_bytes ? src_bytes : dst_bytes;
 
129
        if (src_le) {
 
130
                data->copy_ofs = 4 - data->copy_bytes;
 
131
                data->src_ofs = src_bytes - data->copy_bytes;
 
132
        } else
 
133
                data->src_ofs = snd_pcm_format_physical_width(src_format) / 8 -
 
134
                        src_bytes;
 
135
        if (dst_le)
 
136
                data->dst_ofs = 4 - data->dst_bytes;
 
137
        else
 
138
                data->dst_ofs = snd_pcm_format_physical_width(dst_format) / 8 -
 
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                        dst_bytes;
 
140
        if (snd_pcm_format_signed(src_format) !=
 
141
            snd_pcm_format_signed(dst_format)) {
 
142
                if (dst_le)
 
143
                        data->flip = cpu_to_le32(0x80000000);
 
144
                else
 
145
                        data->flip = cpu_to_be32(0x80000000);
 
146
        }
 
147
}
 
148
 
 
149
int snd_pcm_plugin_build_linear(struct snd_pcm_substream *plug,
 
150
                                struct snd_pcm_plugin_format *src_format,
 
151
                                struct snd_pcm_plugin_format *dst_format,
 
152
                                struct snd_pcm_plugin **r_plugin)
 
153
{
 
154
        int err;
 
155
        struct linear_priv *data;
 
156
        struct snd_pcm_plugin *plugin;
 
157
 
 
158
        if (snd_BUG_ON(!r_plugin))
 
159
                return -ENXIO;
 
160
        *r_plugin = NULL;
 
161
 
 
162
        if (snd_BUG_ON(src_format->rate != dst_format->rate))
 
163
                return -ENXIO;
 
164
        if (snd_BUG_ON(src_format->channels != dst_format->channels))
 
165
                return -ENXIO;
 
166
        if (snd_BUG_ON(!snd_pcm_format_linear(src_format->format) ||
 
167
                       !snd_pcm_format_linear(dst_format->format)))
 
168
                return -ENXIO;
 
169
 
 
170
        err = snd_pcm_plugin_build(plug, "linear format conversion",
 
171
                                   src_format, dst_format,
 
172
                                   sizeof(struct linear_priv), &plugin);
 
173
        if (err < 0)
 
174
                return err;
 
175
        data = (struct linear_priv *)plugin->extra_data;
 
176
        init_data(data, src_format->format, dst_format->format);
 
177
        plugin->transfer = linear_transfer;
 
178
        *r_plugin = plugin;
 
179
        return 0;
 
180
}