diff options
| author | Joel Fernandes <joelf@ti.com> | 2013-09-24 01:05:15 +0200 |
|---|---|---|
| committer | Vinod Koul <vinod.koul@intel.com> | 2013-10-21 09:25:29 +0200 |
| commit | 2abd5f1b97fce6e197be01d67a9567c7793c80d3 (patch) | |
| tree | be4461d09afc0ed1dfe30a5484e8f75099334349 /drivers/dma/edma.c | |
| parent | dma: edma: Split out PaRAM set calculations into its own function (diff) | |
| download | linux-2abd5f1b97fce6e197be01d67a9567c7793c80d3.tar.xz linux-2abd5f1b97fce6e197be01d67a9567c7793c80d3.zip | |
dma: edma: Increase maximum SG limit to 20
davinci-pcm uses 16 as the no.of periods. With this, in EDMA we have to
allocate atleast 17 slots: 1 slot for channel, and 16 slots the periods.
Due to this, the MAX_NR_SG limitation causes problems, set it to 20 to make
cyclic DMA work when davinci-pcm is converted to use DMA Engine. Also add
a comment clarifying this.
Signed-off-by: Joel Fernandes <joelf@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'drivers/dma/edma.c')
| -rw-r--r-- | drivers/dma/edma.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c index e47e3c9e37b2..79b046b3e2f0 100644 --- a/drivers/dma/edma.c +++ b/drivers/dma/edma.c @@ -46,8 +46,14 @@ #define EDMA_CHANS 64 #endif /* CONFIG_ARCH_DAVINCI_DA8XX */ -/* Max of 16 segments per channel to conserve PaRAM slots */ -#define MAX_NR_SG 16 +/* + * Max of 20 segments per channel to conserve PaRAM slots + * Also note that MAX_NR_SG should be atleast the no.of periods + * that are required for ASoC, otherwise DMA prep calls will + * fail. Today davinci-pcm is the only user of this driver and + * requires atleast 17 slots, so we setup the default to 20. + */ +#define MAX_NR_SG 20 #define EDMA_MAX_SLOTS MAX_NR_SG #define EDMA_DESCRIPTORS 16 |