Hello, On Sa, 2016-05-07 at 09:06 +0200, Clemens Ladisch wrote: > Jörg Krause wrote: > > For the softvol plugin the TLV data are written wrong, e.g. for the > > default values > > of min_dB = -51 dB and max_dB = 0 dB, alsactl generates the > > following state: > > > > tlv '00000001000000080000000000000014' > > > > As both min_dB and max_dB can be negative numbers, the tlv type > > must not be > > unsigned. > > TLVs always are unsigned. But they can contain bit patterns that are > to > be interpreted as signed. I see! > > - unsigned int tlv[4]; > > + int tlv[4]; > > tlv[0] = SND_CTL_TLVT_DB_SCALE; > > tlv[1] = 2 * sizeof(int); > > tlv[2] = svol->min_dB * 100; > > The problem is that conversion of a negative floating-point number > into > an unsigned integer results in undefined behaviour, and on your > architecture (whatever it is), this results in zero. > > The correct way to handle this would be something like this: > > tlv[i] = (int)(...); This fixes the issue for my ARM target, many thanks! I'll send an updated version. Many thanks for the review! Best regards, Jörg Krause _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
