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| author | Jaroslav Kysela <perex@suse.cz> | 2006-06-01 18:34:01 +0200 |
|---|---|---|
| committer | Jaroslav Kysela <perex@suse.cz> | 2006-09-23 10:36:42 +0200 |
| commit | 42750b04c5baa7c5ffdf0a8be2b9b320efdf069f (patch) | |
| tree | 52aea8f1eeb44405b67bc5b381cce6bc20e2bff6 /include/sound/tlv.h | |
| parent | 3eeab61aa3ddd3c0bedb7449ada1599de22fdb5a (diff) | |
| download | kernel-crypto-42750b04c5baa7c5ffdf0a8be2b9b320efdf069f.tar.gz kernel-crypto-42750b04c5baa7c5ffdf0a8be2b9b320efdf069f.tar.xz kernel-crypto-42750b04c5baa7c5ffdf0a8be2b9b320efdf069f.zip | |
[ALSA] Control API - TLV implementation for additional information like dB scale
This patch implements a TLV mechanism to transfer an additional information
like dB scale to the user space. The types might be extended in future.
Acked-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
Diffstat (limited to 'include/sound/tlv.h')
| -rw-r--r-- | include/sound/tlv.h | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/include/sound/tlv.h b/include/sound/tlv.h new file mode 100644 index 00000000000..b826e1df1da --- /dev/null +++ b/include/sound/tlv.h @@ -0,0 +1,43 @@ +#ifndef __SOUND_TLV_H +#define __SOUND_TLV_H + +/* + * Advanced Linux Sound Architecture - ALSA - Driver + * Copyright (c) 2006 by Jaroslav Kysela <perex@suse.cz> + * + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +/* + * TLV structure is right behind the struct snd_ctl_tlv: + * unsigned int type - see SNDRV_CTL_TLVT_* + * unsigned int length + * .... data aligned to sizeof(unsigned int), use + * block_length = (length + (sizeof(unsigned int) - 1)) & + * ~(sizeof(unsigned int) - 1)) .... + */ + +#define SNDRV_CTL_TLVT_CONTAINER 0 /* one level down - group of TLVs */ +#define SNDRV_CTL_TLVT_DB_SCALE 1 /* dB scale */ + +#define DECLARE_TLV_DB_SCALE(name, min, step, mute) \ +unsigned int name[] = { \ + SNDRV_CTL_TLVT_DB_SCALE, 2 * sizeof(unsigned int), \ + (min), ((step) & 0xffff) | ((mute) ? 0x10000 : 0) \ +} + +#endif /* __SOUND_TLV_H */ |