In some cases it is desired to move a channel to a specific event queue.
Such a use case is audio, where it is preferred that it is served with
highest priority compared to other DMA clients.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
---
arch/arm/common/edma.c | 28 ++++++++++++++++++++++++++++
include/linux/platform_data/edma.h | 2 ++
2 files changed, 30 insertions(+)
diff --git a/arch/arm/common/edma.c b/arch/arm/common/edma.c
index f834aae7720f..88099175fc56 100644
--- a/arch/arm/common/edma.c
+++ b/arch/arm/common/edma.c
@@ -1414,6 +1414,34 @@ void edma_clear_event(unsigned channel)
}
EXPORT_SYMBOL(edma_clear_event);
+/*
+ * edma_assign_channel_eventq - move given channel to desired eventq
+ * Arguments:
+ * channel - channel number
+ * eventq_no - queue to move the channel
+ *
+ * Can be used to move a channel to a selected event queue.
+ */
+void edma_assign_channel_eventq(unsigned channel, enum dma_event_q eventq_no)
+{
+ unsigned ctlr;
+
+ ctlr = EDMA_CTLR(channel);
+ channel = EDMA_CHAN_SLOT(channel);
+
+ if (channel >= edma_cc[ctlr]->num_channels)
+ return;
+
+ /* default to low priority queue */
+ if (eventq_no == EVENTQ_DEFAULT)
+ eventq_no = edma_cc[ctlr]->default_queue;
+ if (eventq_no >= edma_cc[ctlr]->num_tc)
+ return;
+
+ map_dmach_queue(ctlr, channel, eventq_no);
+}
+EXPORT_SYMBOL(edma_assign_channel_eventq);
+
static int edma_setup_from_hw(struct device *dev, struct edma_soc_info *pdata,
struct edma *edma_cc)
{
diff --git a/include/linux/platform_data/edma.h b/include/linux/platform_data/edma.h
index eb8d5627d080..bdb2710e2aab 100644
--- a/include/linux/platform_data/edma.h
+++ b/include/linux/platform_data/edma.h
@@ -150,6 +150,8 @@ void edma_clear_event(unsigned channel);
void edma_pause(unsigned channel);
void edma_resume(unsigned channel);
+void edma_assign_channel_eventq(unsigned channel, enum dma_event_q eventq_no);
+
struct edma_rsv_info {
const s16 (*rsv_chans)[2];
--
2.0.0
--
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