Hi Kedar,

On Monday 19 Dec 2016 15:39:43 Appana Durga Kedareswara Rao wrote:

Hi Laurent Pinchart,

	Thanks for the review...

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+	if (!chan->idle)
+		return;

Don't you need to perform the same check for the DMA and CDMA channels ?
If so, shouldn't this be moved to common code ?

Will fix it in v2...

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There's another problem (not strictly introduced by this patch) I wanted
to mention. The append_desc_queue() function, called from your tx_submit
handler, appends descriptors to the pending_list. The DMA engine API
states that a transfer submitted by tx_submit will not be executed until
.issue_pending() is called. However, if a transfer is in progress at
tx_submit time, I believe that the IRQ handler, at transfer completion,
will start the next transfer from the pending_list even if
.issue_pending() hasn't been called for it.

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 	if (list_empty(&chan->pending_list))
 		return;

If user submits more than h/w limit then that case only driver will process
The descriptors from the pending_list for other cases the pending_list will
be Empty so driver just returns from there.

I understand that, but that's not the problem. Your .tx_submit() handler calls 
append_desc_queue() which adds the tx descriptor to the pending_list. If a 
transfer is in progress at that time, I believe the transfer completion IRQ 
handler will take the next descriptor from the pending_list and process it, 
even though issue_pending() hasn't been called for it.

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Now that you catch busy channels with a software flag, do you still need
the xilinx_dma_is_running() and xilinx_dma_is_idle() checks ? Three
different checks for the same or very similar conditions are confusing,
if you really need them you should document clearly how they differ.

Will remove the xilinx_dma_is_running and xilinx_dmais_idle() checks and
will use Chan->idle check across all the IP's. Will fix it v2...

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@@ -1110,6 +1116,7 @@ static void xilinx_vdma_start_transfer(struct

xilinx_dma_chan *chan) vdma_desc_write(chan, XILINX_DMA_REG_VSIZE,
last->hw.vsize);

 	}

+	chan->idle = false;

(and this too)

Will fix in v2...

-- 
Regards,

Laurent Pinchart