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authorSascha Hauer2009-11-18 15:21:44 +0100
committerSascha Hauer2009-11-24 08:40:14 +0100
commit4998f1a30cf8e21c5bc0766fde4fa58e1adabd72 (patch)
treec58feecc32d7fbe7d128094a72ff9e4471fcdd3d /arch/arm/plat-mxc/include/mach/dma-mx1-mx2.h
parenti.MX31 clock: rename SSI clocks to driver name (diff)
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mxc: mx1/mx2 DMA: add a possibility to create an endless DMA transfer
This is useful for audio where we do not want to setup a new scatterlist after playing 4GB of audio data. This would cause skips in the playback. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'arch/arm/plat-mxc/include/mach/dma-mx1-mx2.h')
-rw-r--r--arch/arm/plat-mxc/include/mach/dma-mx1-mx2.h8
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/arm/plat-mxc/include/mach/dma-mx1-mx2.h b/arch/arm/plat-mxc/include/mach/dma-mx1-mx2.h
index b3876cc238ca..07be8ad7ec37 100644
--- a/arch/arm/plat-mxc/include/mach/dma-mx1-mx2.h
+++ b/arch/arm/plat-mxc/include/mach/dma-mx1-mx2.h
@@ -58,6 +58,14 @@ imx_dma_setup_single(int channel, dma_addr_t dma_address,
unsigned int dma_length, unsigned int dev_addr,
unsigned int dmamode);
+
+/*
+ * Use this flag as the dma_length argument to imx_dma_setup_sg()
+ * to create an endless running dma loop. The end of the scatterlist
+ * must be linked to the beginning for this to work.
+ */
+#define IMX_DMA_LENGTH_LOOP ((unsigned int)-1)
+
int
imx_dma_setup_sg(int channel, struct scatterlist *sg,
unsigned int sgcount, unsigned int dma_length,