Re: [PATCH 4/4] dmaengine: pxa_dma: fix the maximum requestor line

Vinod Koul [off-list ref] writes:

On Mon, Feb 15, 2016 at 06:24:57PM +0100, Robert Jarzmik wrote:

quoted

Vinod Koul [off-list ref] writes:

quoted

On Thu, Feb 11, 2016 at 10:23:18PM +0100, Robert Jarzmik wrote:

quoted

@@ -1399,13 +1405,17 @@ static int pxad_probe(struct platform_device *op)
 		return PTR_ERR(pdev->base);
 
 	of_id = of_match_device(pxad_dt_ids, &op->dev);
-	if (of_id)
+	if (of_id) {
 		of_property_read_u32(op->dev.of_node, "#dma-channels",
 				     &dma_channels);
-	else if (pdata && pdata->dma_channels)
+		of_property_read_u32(op->dev.of_node, "#requestors",
+				     &nb_requestors);

I think we should check the return value here. This might be err in case
when we have older DT on platform, but still should work with default in
that case

Okay, but how should the code react to the err case, more specifically to
-EINVAL or -ENODATA ? As this property is optional as per the device-tree
description, the current code leaves nb_requestors = 0, as is specified in the
description, and fits the mmp_pdma case.

What do you think should be done ? A warning message ? Something else ?

Message is fine, but in order for not to regress we should set this to 32
(IIRC default before this, right) and not zero.

Okay, got you.

For v2 I'll implement exactly this, ie. a warning message and a default to 32.
I'll amend the device-tree description also to match the 32 (and not the 0 I
wrote earlier).

Cheers.

-- 
Robert