On Mon, 10 Aug 2009 10:50:04 +0200 Janusz Krzysztofik jkrzyszt@tis.icnet.pl wrote:
Use newly implemented DMA channel self linking on OMAP1510 like on other OMAP models. Remove unnecessary DMA transfer restart from interrupt handler routine.
The interrupt routine used to maintain a period index, originally needed for counting up periods up to a full buffer in order to restart the DMA transfer. For some time, this counter is also used as a replacement for hardware DMA progress counter that has been found unusable on OMAP1510 in case of playback. Thus, the period index calculation cannot be omitted completely. However, the accuracy of this counter can still suffer from missing DMA interrupts.
In order to work correctly, it requires patch 1 from this series also applied: [RFC][PATCH 1/3] ARM: OMAP: DMA: Add support for DMA channel self linking on OMAP1510
Created against linux-2.6.31-rc5.
Tested on Amstrad Delta.
Signed-off-by: Janusz Krzysztofik jkrzyszt@tis.icnet.pl
Nice to see code to be more uniform across the OMAP's. Note this depends on patch 1 which touches the arch/arm/plat-omap/dma.c.
Acked-by: Jarkko Nikula jhnikula@gmail.com