ARM: SAMSUNG: Add device tree support for pl330 dma engine wrappers
A new dma request id 'DMACH_DT_PROP' is introduced for client drivers
requesting a dma channel. This request indicates that a device tree
node property represting the dma channel is available in
'struct samsung_dma_info'. The dma channel request wrapper uses the
node property value as the value for the filter parameter.
Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
diff --git a/arch/arm/plat-samsung/dma-ops.c b/arch/arm/plat-samsung/dma-ops.c
index 889c2c2..2cded87 100644
--- a/arch/arm/plat-samsung/dma-ops.c
+++ b/arch/arm/plat-samsung/dma-ops.c
@@ -24,11 +24,18 @@
struct dma_chan *chan;
dma_cap_mask_t mask;
struct dma_slave_config slave_config;
+ void *filter_param;
dma_cap_zero(mask);
dma_cap_set(info->cap, mask);
- chan = dma_request_channel(mask, pl330_filter, (void *)dma_ch);
+ /*
+ * If a dma channel property of a device node from device tree is
+ * specified, use that as the fliter parameter.
+ */
+ filter_param = (dma_ch == DMACH_DT_PROP) ? (void *)info->dt_dmach_prop :
+ (void *)dma_ch;
+ chan = dma_request_channel(mask, pl330_filter, filter_param);
if (info->direction == DMA_FROM_DEVICE) {
memset(&slave_config, 0, sizeof(struct dma_slave_config));
diff --git a/arch/arm/plat-samsung/include/plat/dma-ops.h b/arch/arm/plat-samsung/include/plat/dma-ops.h
index 4c1a363..22eafc3 100644
--- a/arch/arm/plat-samsung/include/plat/dma-ops.h
+++ b/arch/arm/plat-samsung/include/plat/dma-ops.h
@@ -31,6 +31,7 @@
enum dma_slave_buswidth width;
dma_addr_t fifo;
struct s3c2410_dma_client *client;
+ struct property *dt_dmach_prop;
};
struct samsung_dma_ops {
diff --git a/arch/arm/plat-samsung/include/plat/dma-pl330.h b/arch/arm/plat-samsung/include/plat/dma-pl330.h
index 2e55e59..c5eaad5 100644
--- a/arch/arm/plat-samsung/include/plat/dma-pl330.h
+++ b/arch/arm/plat-samsung/include/plat/dma-pl330.h
@@ -21,7 +21,8 @@
* use these just as IDs.
*/
enum dma_ch {
- DMACH_UART0_RX,
+ DMACH_DT_PROP = -1,
+ DMACH_UART0_RX = 0,
DMACH_UART0_TX,
DMACH_UART1_RX,
DMACH_UART1_TX,