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authorMika Westerberg2011-05-29 12:10:06 +0200
committerGrant Likely2011-06-08 23:46:12 +0200
commit626a96db11698119a67eeda130488e869aa6f14e (patch)
tree1d5fd7da4a7919596bd81e0136d96679196e1152 /Documentation/spi
parentep93xx: remove the old M2P DMA code (diff)
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spi/ep93xx: add DMA support
This patch adds DMA support for the EP93xx SPI driver. By default the DMA is not enabled but it can be enabled by setting ep93xx_spi_info.use_dma to true in board configuration file. Note that the SPI driver still uses PIO for small transfers (<= 8 bytes) for performance reasons. Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi> Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com> Acked-by: Vinod Koul <vinod.koul@intel.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Diffstat (limited to 'Documentation/spi')
-rw-r--r--Documentation/spi/ep93xx_spi10
1 files changed, 10 insertions, 0 deletions
diff --git a/Documentation/spi/ep93xx_spi b/Documentation/spi/ep93xx_spi
index 6325f5b48635..d8eb01c15db1 100644
--- a/Documentation/spi/ep93xx_spi
+++ b/Documentation/spi/ep93xx_spi
@@ -88,6 +88,16 @@ static void __init ts72xx_init_machine(void)
ARRAY_SIZE(ts72xx_spi_devices));
}
+The driver can use DMA for the transfers also. In this case ts72xx_spi_info
+becomes:
+
+static struct ep93xx_spi_info ts72xx_spi_info = {
+ .num_chipselect = ARRAY_SIZE(ts72xx_spi_devices),
+ .use_dma = true;
+};
+
+Note that CONFIG_EP93XX_DMA should be enabled as well.
+
Thanks to
=========
Martin Guy, H. Hartley Sweeten and others who helped me during development of