Re: [RFC v02 04/15] dmaengine: edma: Add support for DMA filter mapping to slave devices

Vinod Koul
2015-12-01T17:20:01Z

On Mon, Nov 30, 2015 at 03:45:34PM +0200, Peter Ujfalusi wrote:
> Add support for providing device to filter_fn mapping so client drivers
> can switch to use the dma_request_chan() API.

Any reason why we dont want to go with DT based only for edma here?

>
> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
> ---
> drivers/dma/edma.c | 24 ++++++++++++++++++++++++
> include/linux/platform_data/edma.h | 5 +++++
> 2 files changed, 29 insertions(+)
>
> diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c
> index 0675e268d577..386f8c9bd606 100644
> --- a/drivers/dma/edma.c
> +++ b/drivers/dma/edma.c
> @@ -2098,6 +2098,8 @@ static struct dma_chan *of_edma_xlate(struct of_phandle_args *dma_spec,
> }
> #endif
>
> +static bool edma_filter_for_map(struct dma_chan *chan, void *param);
> +
> static int edma_probe(struct platform_device *pdev)
> {
> struct edma_soc_info *info = pdev->dev.platform_data;
> @@ -2297,6 +2299,12 @@ static int edma_probe(struct platform_device *pdev)
> edma_set_chmap(&ecc->slave_chans[i], ecc->dummy_slot);
> }
>
> + if (info->filter_map) {
> + ecc->dma_slave.filter_map.map = info->filter_map;
> + ecc->dma_slave.filter_map.mapcnt = info->filtercnt;
> + ecc->dma_slave.filter_map.filter_fn = edma_filter_for_map;
> + }
> +
> ret = dma_async_device_register(&ecc->dma_slave);
> if (ret) {
> dev_err(dev, "slave ddev registration failed (%d)\n", ret);
> @@ -2428,6 +2436,22 @@ bool edma_filter_fn(struct dma_chan *chan, void *param)
> }
> EXPORT_SYMBOL(edma_filter_fn);
>
> +static bool edma_filter_for_map(struct dma_chan *chan, void *param)
> +{
> + bool match = false;
> +
> + if (chan->device->dev->driver == &edma_driver.driver) {
> + struct edma_chan *echan = to_edma_chan(chan);
> + unsigned ch_req = (unsigned)param;
> + if (ch_req == echan->ch_num) {
> + /* The channel is going to be used as HW synchronized */
> + echan->hw_triggered = true;
> + match = true;
> + }
> + }
> + return match;
> +}
> +
> static int edma_init(void)
> {
> int ret;
> diff --git a/include/linux/platform_data/edma.h b/include/linux/platform_data/edma.h
> index e2878baeb90e..117a36d63840 100644
> --- a/include/linux/platform_data/edma.h
> +++ b/include/linux/platform_data/edma.h
> @@ -59,6 +59,8 @@ struct edma_rsv_info {
> const s16 (*rsv_slots)[2];
> };
>
> +struct dma_filter_map;
> +
> /* platform_data for EDMA driver */
> struct edma_soc_info {
> /*
> @@ -76,6 +78,9 @@ struct edma_soc_info {
>
> s8 (*queue_priority_mapping)[2];
> const s16 (*xbar_chans)[2];
> +
> + struct dma_filter_map *filter_map;
> + int filtercnt;
> };
>
> #endif
> --
> 2.6.3
>

--
~Vinod