On Thu, 2010-06-03 at 07:39 +0300, Peter Ujfalusi wrote: > Hello, > > Tony: Could you take a look at the arch/arm patches in this series? > Thanks! > > Changes since v3/4: > - Fixed commit subjects and messages for OMAP3 related patches > - Added Acked-by from Mark, and Jarkko > > Intro message from the original series: > > This series aims to correct how the McBSP FIFO is viewed, and handled. > > Introduction of the problem: > OMAP McBSP FIFO is word structured: > McBSP2 has 1024 + 256 = 1280 word long buffer, > McBSP1,3,4,5 has 128 word long buffer > > This means, that the size of the FIFO > depends on the McBSP word size configuration. > For example on McBSP3: > 16bit samples: size is 128 * 2 = 256 bytes > 32bit samples: size is 128 * 4 = 512 bytes > It is simpler to place constraint for buffer and period based on channels. > McBSP3 as example again (16 or 32 bit samples): > 1 channel (mono): size is 128 frames (128 words) > 2 channels (stereo): size is 128 / 2 = 64 frames (2 * 64 words) > 4 channels: size is 128 / 4 = 32 frames (4 * 32 words) > > Since now the McBSP codec supports not only 16bit samples (32biut has been > recently added), the FIFO size handling is no longer correct, since it has > been hard wired for 16bit word length. > > The series changes how the users of McBSP are configuring the FIFO: > It used to be 0 based (0 meant 1 word threshold). After this series users can > configure the threshold in 1 base mode (1 means 1 word threshold). > The platform code now provides the full size of the FIFO in words, instead of > the already limited value used in the past. > > In ASoC omap-mcbsp code hw_rule based constraint refinement is going to be used > instead of the hardwired static constraint, which was correct only in case of > 16bit word length. > > The hw_rule is refining the minimum buffer size based on the channel number > going to be used by the coming stream. > In case of threshold mode additional hw_rule refines the maximum allowed period > size. > > The series are generated agains Takashi's sound-2.6: topic/asoc branch. > > CCing also Eduardo, and Eero since they have worked on the original > FIFO/threshold implementation. > > All commetns and testers are welcome! > Peter > > --- > Peter Ujfalusi (5): > OMAP: McBSP: Function to query the FIFO size > OMAP3: McBSP: Change the way how the FIFO is handled > OMAP3: McBSP: Use the port's buffer_size when calculating tx delay > ASoC: omap-mcbsp: Save, and use wlen for threshold configuration > ASoC: omap-mcbsp: Place correct constraints for streams > > arch/arm/mach-omap2/mcbsp.c | 10 ++-- > arch/arm/plat-omap/include/plat/mcbsp.h | 2 + > arch/arm/plat-omap/mcbsp.c | 51 ++++++++++----- > sound/soc/omap/omap-mcbsp.c | 112 +++++++++++++++++++++++------- > 4 files changed, 128 insertions(+), 47 deletions(-) > Applied all. Thanks Liam -- Freelance Developer, SlimLogic Ltd ASoC and Voltage Regulator Maintainer. http://www.slimlogic.co.uk -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
