On Thu, Oct 20, 2016 at 02:34:34PM +0300, Jani Nikula wrote: > On Thu, 20 Oct 2016, "Yang, Libin" <libin.yang@xxxxxxxxx> wrote: > >> >> Any particular reason these M/N values are half of what they're in > >> >> table > >> >> 2-104 of DP 1.4 spec? (Admittedly the table is an informative > >> >> example.) > >> > > >> > For HDMI, we found only set N is enough. HW then can handle the > >> remaining. > >> > >> I meant, the M and N values in this part of the dp_aud_n_m table are 1/2 of > >> what they are in the DP spec table. Why? > > > > Which table are you meaning? I calculate the values myself. I didn't find the > > full table in DP spec. I only find the table for 270MHz and 162MHz in > > Table 2-50: Examples of Maud and Naud Values > > Table 2-104 in DP 1.4. Maybe you're looking at an older version of the > spec. So it looks like they used the same M value for all link frequencies in that example, which for 540M ends up being double what the minimal accurate value is. But as both M and N are doubled the ratio is still exactly the same. And there is indeed a 64k and 128k bitrates added as well. Those are not classified under HBR audio. But as those can't be expressed via short audio descriptors in the EDID, I don't think they would be accepted by ALSA. Or am I wrong? I do wonder how they are supposed to be used though since there must be some way for the sink to advertise them, otherwise I can't see the point in adding them. -- Ville Syrjälä Intel OTC _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
