[PATCH RFC 2/2] ARM: pxa: transition to dmaengine phase 1

From: Robert Jarzmik
Date: Sat Feb 14 2015 - 17:48:18 EST


In order to slowly transition pxa to dmaengine, the legacy code will now
rely on dmaengine to request a channel.

This implies that PXA architecture selects DMADEVICES and MMP_PDMA,
which is not pretty. Yet it enables PXA drivers to be ported one by one,
with part of them using dmaengine, and the other part using the legacy
code.

Signed-off-by: Robert Jarzmik <robert.jarzmik@xxxxxxx>
---
arch/arm/Kconfig | 2 ++
arch/arm/plat-pxa/dma.c | 4 +++-
arch/arm/plat-pxa/include/plat/dma.h | 1 +
3 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index bb358d2..cc23f2b 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -617,10 +617,12 @@ config ARCH_PXA
select CLKDEV_LOOKUP
select CLKSRC_MMIO
select CLKSRC_OF
+ select DMADEVICES
select GENERIC_CLOCKEVENTS
select GPIO_PXA
select HAVE_IDE
select IRQ_DOMAIN
+ select MMP_PDMA
select MULTI_IRQ_HANDLER
select PLAT_PXA
select SPARSE_IRQ
diff --git a/arch/arm/plat-pxa/dma.c b/arch/arm/plat-pxa/dma.c
index 054fc5a..e5094a6 100644
--- a/arch/arm/plat-pxa/dma.c
+++ b/arch/arm/plat-pxa/dma.c
@@ -294,7 +294,8 @@ int pxa_request_dma (char *name, pxa_dma_prio prio,
/* try grabbing a DMA channel with the requested priority */
for (i = 0; i < num_dma_channels; i++) {
if ((dma_channels[i].prio == prio) &&
- !dma_channels[i].name) {
+ !dma_channels[i].name &&
+ !mmp_pdma_toggle_reserved_channel(i)) {
found = 1;
break;
}
@@ -331,6 +332,7 @@ void pxa_free_dma (int dma_ch)
local_irq_save(flags);
DCSR(dma_ch) = DCSR_STARTINTR|DCSR_ENDINTR|DCSR_BUSERR;
dma_channels[dma_ch].name = NULL;
+ mmp_pdma_toggle_reserved_channel(dma_ch);
local_irq_restore(flags);
}
EXPORT_SYMBOL(pxa_free_dma);
diff --git a/arch/arm/plat-pxa/include/plat/dma.h b/arch/arm/plat-pxa/include/plat/dma.h
index a7b91dc..f4c6339 100644
--- a/arch/arm/plat-pxa/include/plat/dma.h
+++ b/arch/arm/plat-pxa/include/plat/dma.h
@@ -81,5 +81,6 @@ int pxa_request_dma (char *name,
void *data);

void pxa_free_dma (int dma_ch);
+extern int mmp_pdma_toggle_reserved_channel(int legacy_channel);

#endif /* __PLAT_DMA_H */
--
2.1.0

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/