In commit bf1d1c9b61 ("ALSA: tlv: add DECLARE_TLV_DB_RANGE()"), the new
macro was added so that "dB range information can be specified without
having to count the items manually for TLV_DB_RANGE_HEAD()". In short,
TLV_DB_RANGE_HEAD macro was obsoleted.
In commit 46e860f768 ("ALSA: rename TLV-related macros so that they're
friendly to user applications"), TLV-related macros are exposed for
applications in user land to get content of data structured by
Type/Length/Value shape. The commit managed to expose TLV-related macros
as many as possible, while obsoleted TLV_DB_RANGE_HEAD() was included to
the list of exposed macros.
This situation brings some confusions to application developers because
they might think all exposed macros have their own purpose and useful for
applications.
For the reason, this commit moves TLV_DB_RANGE_HEAD macro from UAPI header
to a header for kernel land, again. The above commit is done within the
same development period for kernel 4.9, thus not published yet. This
commit might certainly brings no confusions to user land.
Reference: commit bf1d1c9b61 ("ALSA: tlv: add DECLARE_TLV_DB_RANGE()")
Reference: commit 46e860f768 ("ALSA: rename TLV-related macros so that they're friendly to user applications")
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
In a previous commit, some macros newly appeared to UAPI header for TLV
packet. These macros have short names and they easily bring name conflist
to applications. The conflict can be avoided to rename them with a proper
prefix.
For this purpose, this commit renames these macros with prefix
'SNDRV_CTL_TLVD_'.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
In ALSA control interface, each element set can have threshold level
information. This information is transferred between drivers/applications,
in a shape of tlv packet. The layout of this packet is defined in
'uapi/sound/asound.h' (struct snd_ctl_tlv):
struct snd_ctl_tlv {
unsigned int numid;
unsigned int length;
unsigned int tlv[0];
};
Data in the payload (struct snd_ctl_tlv.tlv) is expected to be filled
according to our own protocol. This protocol is described in
'include/sound/tlv.h'. A layout of the payload is expected as:
struct snd_ctl_tlv.tlv[0]: one of SNDRV_CTL_TLVT_XXX
struct snd_ctl_tlv.tlv[1]: Length of data
struct snd_ctl_tlv.tlv[2...]: data
Unfortunately, the macro is not exported to user land yet, thus
applications cannot get to know the protocol.
Additionally, ALSA control core has a feature called as 'user-defined'
element set. This allows applications to add/remove arbitrary element sets
with elements to control devices. Elements in the element set can be
operated by the same way as the ones added by in-kernel implementation.
For threshold level information of 'user-defined' element set, applications
need to register the information to an element set. However, as described
above, layout of the payload is closed in kernel land. This is quite
inconvenient, too.
This commit moves the protocol to UAPI header for TLV.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Make sure userspace can define TLV controls for topology using the correct
type numbers and channel mappings.
Signed-off-by: Liam Girdwood <liam.r.girdwood@linux.intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Takashi Sakamoto