At Wed, 19 Aug 2009 12:48:26 +0000, Shine Liu wrote: > > On Wed, 2009-08-19 at 14:05 +0200, Takashi Iwai wrote: > > > > > > But the irq last issued should be at 0x3e80, but not 0x3800 + 0x800 = > > > 0x4000. The DMA engine loaded 0x680 frame not 0x800 frame at the last > > > time. > > > > Then it's a driver bug. If unaligned period size is allowed, it means > > that the irq is really generated in that period, not at the buffer > > boundary. Otherwise, it must have a proper hw-constraint to align the > > period size to the buffer size. > > > > What hardware is it? > > Yes, but there's no constraint code currently to force to align the > period size to the buffer size. The bug occurs on linux-2.6.31-rc6 on > ASoC s3c24xx platform. > > The constraint to force to align the period size to the buffer size > should not be hardware depended, it shoud be done in the generic layer, > is it? It is hardware dependent, i.e. how the irq is generated. If the irq is generated in a way like timer, the period size doesn't have to be aligned with the buffer size. But your case doesn't look like that. Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
