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

Peter Ujfalusi
2015-11-30T13:45:34Z

Add support for providing device to filter_fn mapping so client drivers
can switch to use the dma_request_chan() API.

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