summaryrefslogtreecommitdiffstats
path: root/Documentation/spi
diff options
context:
space:
mode:
authorMika Westerberg <mika.westerberg@iki.fi>2011-05-29 13:10:06 +0300
committerGrant Likely <grant.likely@secretlab.ca>2011-06-08 15:46:12 -0600
commit626a96db11698119a67eeda130488e869aa6f14e (patch)
tree1d5fd7da4a7919596bd81e0136d96679196e1152 /Documentation/spi
parent71cebd700257a4f644066631bf02187d8f67817e (diff)
downloadop-kernel-dev-626a96db11698119a67eeda130488e869aa6f14e.zip
op-kernel-dev-626a96db11698119a67eeda130488e869aa6f14e.tar.gz
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 6325f5b..d8eb01c 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
OpenPOWER on IntegriCloud