[PATCH -next 6/8] dmaengine: xilinx_dma: Print debug message when no free tx segments

From: Radhey Shyam Pandey
Date: Thu Sep 05 2019 - 12:37:50 EST


From: Nicholas Graumann <nick.graumann@xxxxxxxxx>

The driver should not run out of tx segments in normal operation. But,
if the user attempts to prepare a transaction with a large sg list,
the driver may not have enough free segments to accommodate the request.

Log a message at the debug level to inform the user in case they are
experiencing issues.

Signed-off-by: Nicholas Graumann <nick.graumann@xxxxxxxxx>
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xxxxxxxxxx>
---
drivers/dma/xilinx/xilinx_dma.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c
index bf3fa2e..b5dd62a 100644
--- a/drivers/dma/xilinx/xilinx_dma.c
+++ b/drivers/dma/xilinx/xilinx_dma.c
@@ -612,6 +612,9 @@ xilinx_axidma_alloc_tx_segment(struct xilinx_dma_chan *chan)
}
spin_unlock_irqrestore(&chan->lock, flags);

+ if (!segment)
+ dev_dbg(chan->dev, "Could not find free tx segment\n");
+
return segment;
}

--
2.7.4