Re: [PATCH V2 2/3] dmaengine: dw_dmac: Enhance device tree support

Andy Shevchenko
2012-10-12T14:58:26Z

On Fri, 2012-10-12 at 20:01 +0530, Viresh Kumar wrote:

> diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c

> @@ -1179,6 +1179,53 @@ static void dwc_free_chan_resources(struct dma_chan *chan)
> dev_vdbg(chan2dev(chan), "%s: done\n", __func__);
> }
>
> +bool dw_dma_generic_filter(struct dma_chan *chan, void *param)
> +{
> + struct dw_dma *dw = to_dw_dma(chan->device);
> + static struct dw_dma *last_dw;
> + static char *last_bus_id;
> + int i = -1;
> +
> + /*
> + * dmaengine framework calls this routine for all channels of all dma
> + * controller, until true is returned. If 'param' bus_id is not
> + * registered with a dma controller (dw), then there is no need of
> + * running below function for all channels of dw.
> + *
> + * This block of code does this by saving the parameters of last
> + * failure. If dw and param are same, i.e. trying on same dw with
> + * different channel, return false.
> + */
> + if (last_dw) {
> + if ((last_bus_id == param) && (last_dw == dw))
> + return false;
> + }
Just came to my mind.
dw can't be NULL, can't it?
Then
if (last_dw) {
...
}
is unneeded.

Please, check twice my thought because it's a Friday evening.

> @@ -1462,6 +1509,91 @@ static void dw_dma_off(struct dw_dma *dw)
> dw->chan[i].initialized = false;
> }
>
> +#ifdef CONFIG_OF
> +static struct dw_dma_platform_data *
> +__devinit dw_dma_parse_dt(struct platform_device *pdev)
> +{
> + struct device_node *sn, *cn, *np = pdev->dev.of_node;
> + struct dw_dma_platform_data *pdata;
> + struct dw_dma_slave *sd;
> + u32 val, arr[4];
Let me weekend to think about naming. I really can't offer anything else
right now.

--
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy