On Thu, Sep 15, 2016 at 10:45:49PM +0900, Takashi Sakamoto wrote: > SND_SOC_BYTES_TLV brings confusions to user land because it doesn't follow > to a protocol of ctl and tlv operation. At least, this macro and related > kernel APIs include two misunderstandings: > - 'struct snd_ctl_elem_info.count' can also represent the length of TLV > packet paylaod, snd_soc_bytes_info_ext() performs in this way. > - 'struct snd_ctl_tlv.tlv' can include arbitrary data regardless of TLV > packet structure, snd_soc_bytes_tlv_callback() performs in this way. > > In a policy of kernel land development, it's quite worse to break protocols > for applications. Therefore, developers are discouraged to use these kernel > APIs. > > In the first place, SND_SOC_BYTES_TLV was added to satisfy a request of > developers who need to add control elements which transfer data larger than > the size which 'struct snd_ctl_elem_value' can represent; e.g. over 512 > bytes. However, as long as the size is less than the size; e.g. 512 bytes, > SND_SOC_BYTES_EXT is still available. Although there is actually the > limitation of maximum data size, it's better to use this API for stable > application interface till better alternative ways are implemented in > future. > > For these reasons, this commit reverts the previous commit which lead > developers to the worse behaviour. > > Signed-off-by: Takashi Sakamoto <o-takashi@xxxxxxxxxxxxx> > --- Acked-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxxxxxxxx> Yeah would be better to use normal controls for <512 bytes, so this looks good to me. Although you might want to resend using Mark's kernel.org address as I imagine he would be the one to apply the change and that is the address he normally uses for patches. Thanks, Charles _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
