On Mon, Jun 08, 2009 at 10:13:25PM +0800, Eric Miao wrote: > On Mon, Jun 8, 2009 at 8:12 PM, pHilipp Zabel<philipp.zabel@xxxxxxxxx> wrote: > > Agreed. Also, if I had to use this to configure magician with DSP_A > > (right now it says I2S and LEFT_J only, but why limit it to that?), > > I'd need an additional PXA_SSP_FRM_16FS. > That shouldn't be a problem - it can just be added. That won't scale in a bitmask - as you get more and more slots in use on a TDM system more and more slots are going to need to extend the range of values you can set in a bitmask. Consider what happens when people start hanging 5.1 CODECs off TDM buses with single data lines, for example. > >> sample width parameter to set_tdm_slot() - given the very small number > >> of in tree users it'd cause little disruption. A set_sample_width() > >> operation could also be added. > Well, the real problem is that it's quite difficult to abstract all > the different formats into a single structure. I'd prefer to have > something specific at the begining. I don't see much difference between any of the proposals here (or any problem with format-specificness) - my main thing here is to pull the frame width configuration out of the DAI format. > > set_sample_width or set_frame_width? > > I'd prefer a separate operation over a parameter to set_tdm_slot because > > in my setup I just need to force the (SSP) frame width to 16 bits. > > Enabling network mode and calling set_tdm_slot(..,1,1) wouldn't be > > necessary at all, then. > As said, if we can invent something like a single structure > making all formats happy, it will be good. However, before > that's possible, I'd really prefer less API for the formats being > further introduced, so we go no further from that goal. Well, if we want to avoid introducing a new API at all then the PXA SSP driver is going to need to figure out the bit clock rate automatically from the TDM and sample size configuration - if it needs to be explicitly specified then it's a new API and once we introduce one way of doing this it'll probably stick. TDM really needs some sort of frame/sample width configuration to work well so I think we're better off adding a standard API now. _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
