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

From: Vinod Koul
Date: Mon Feb 15 2016 - 12:29:26 EST


On Mon, Feb 15, 2016 at 06:24:57PM +0100, Robert Jarzmik wrote:
> Vinod Koul <vinod.koul@xxxxxxxxx> writes:
>
> > On Thu, Feb 11, 2016 at 10:23:18PM +0100, Robert Jarzmik wrote:
> >> @@ -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.

--
~Vinod