[v3] ad7877: keep dma rx buffers in seperate cache lines

Commit Message

David Woodhouse May 19, 2010, 1 p.m. UTC

None

Patch

diff --git a/drivers/input/touchscreen/ad7877.c b/drivers/input/touchscreen/ad7877.c
index 0d2d7e5..ae5d56e 100644
--- a/drivers/input/touchscreen/ad7877.c
+++ b/drivers/input/touchscreen/ad7877.c
@@ -151,6 +151,11 @@  enum {
 /*
  * Non-touchscreen sensors only use single-ended conversions.
  */
+#ifdef ARCH_KMALLOC_MINALIGN
+#define __dma_aligned __attribute__((__aligned__(ARCH_KMALLOC_MINALIGN)))
+#else
+#define __dma_aligned
+#endif
 
 struct ser_req {
 	u16			reset;
@@ -163,7 +168,7 @@  struct ser_req {
 	 * DMA (thus cache coherency maintenance) requires the
 	 * transfer buffers to live in their own cache lines.
 	 */
-	u16 sample ____cacheline_aligned;
+	u16 sample __dma_aligned;
 };
 
 struct ad7877 {
@@ -203,7 +208,7 @@  struct ad7877 {
 	 * DMA (thus cache coherency maintenance) requires the
 	 * transfer buffers to live in their own cache lines.
 	 */
-	u16 conversion_data[AD7877_NR_SENSE] ____cacheline_aligned;
+	u16 conversion_data[AD7877_NR_SENSE] __dma_aligned;
 };
 
 static int gpio3;