[PATCH v4 3/6] ARM: edma: Add function to manually trigger an EDMA channel

[Joel Fernandes]

Manual trigger for events missed as a result of splitting a
scatter gather list and DMA'ing it in batches. Add a helper
function to trigger a channel incase any such events are missed.

Signed-off-by: Joel Fernandes <joelf at ti.com>
---
 arch/arm/common/edma.c             | 17 +++++++++++++++++
 include/linux/platform_data/edma.h |  2 ++
 2 files changed, 19 insertions(+)

diff --git a/arch/arm/common/edma.c b/arch/arm/common/edma.c
index 3567ba1..67e8cf5 100644
--- a/arch/arm/common/edma.c
+++ b/arch/arm/common/edma.c
@@ -1236,6 +1236,23 @@ void edma_resume(unsigned channel)
 }
 EXPORT_SYMBOL(edma_resume);
 
+int edma_trigger_channel(unsigned channel)
+{
+	unsigned ctlr;
+	unsigned int mask;
+
+	ctlr = EDMA_CTLR(channel);
+	channel = EDMA_CHAN_SLOT(channel);
+	mask = BIT(channel & 0x1f);
+
+	edma_shadow0_write_array(ctlr, SH_ESR, (channel >> 5), mask);
+
+	pr_debug("EDMA: ESR%d %08x\n", (channel >> 5),
+		 edma_shadow0_read_array(ctlr, SH_ESR, (channel >> 5)));
+	return 0;
+}
+EXPORT_SYMBOL(edma_trigger_channel);
+
 /**
  * edma_start - start dma on a channel
  * @channel: channel being activated
diff --git a/include/linux/platform_data/edma.h b/include/linux/platform_data/edma.h
index 57300fd..179fb91 100644
--- a/include/linux/platform_data/edma.h
+++ b/include/linux/platform_data/edma.h
@@ -180,4 +180,6 @@ struct edma_soc_info {
 	const s16	(*xbar_chans)[2];
 };
 
+int edma_trigger_channel(unsigned);
+
 #endif
-- 
1.8.1.2