When stopping a DMA transfer with interrupts disabled it is possible
that the DMA transfer completes before the events are cleared. In
this case the completion interrupt will be pending, causing a
completion callback after the transfer was stopped.
By clearing the completion interrupt for the stopping channel it is
ensured that no completion event will be generated after the stop.
Signed-off-by: John Ogness <john.ogness@xxxxxxxxxxxxx>
---
arch/arm/common/edma.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/arm/common/edma.c b/arch/arm/common/edma.c
index 5662a87..873dbfc 100644
--- a/arch/arm/common/edma.c
+++ b/arch/arm/common/edma.c
@@ -1350,6 +1350,9 @@ void edma_stop(unsigned channel)
edma_shadow0_write_array(ctlr, SH_SECR, j, mask);
edma_write_array(ctlr, EDMA_EMCR, j, mask);
+ /* clear possibly pending completion interrupt */
+ edma_shadow0_write_array(ctlr, SH_ICR, j, mask);
+
pr_debug("EDMA: EER%d %08x\n", j,
edma_shadow0_read_array(ctlr, SH_EER, j));
--
1.7.10.4
--
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