[PATCH v2 06/19] dmaengine: of-dma: Add support for optional router configuration callback
From: Peter Ujfalusi <hidden>
Date: 2020-11-17 10:56:47
Also in:
dmaengine, linux-devicetree, lkml
Subsystem:
dma generic offload engine subsystem, the rest · Maintainers:
Vinod Koul, Linus Torvalds
Additional configuration for the DMA event router might be needed for a channel which can not be done during device_alloc_chan_resources callback since the router information is not yet present for the drivers. If there is a need for additional configuration for the channel if DMA router is in use, then the driver can implement the device_router_config callback. Signed-off-by: Peter Ujfalusi <redacted> --- drivers/dma/of-dma.c | 10 ++++++++++ include/linux/dmaengine.h | 2 ++ 2 files changed, 12 insertions(+)
diff --git a/drivers/dma/of-dma.c b/drivers/dma/of-dma.c
index 8a4f608904b9..ec00b20ae8e4 100644
--- a/drivers/dma/of-dma.c
+++ b/drivers/dma/of-dma.c@@ -75,8 +75,18 @@ static struct dma_chan *of_dma_router_xlate(struct of_phandle_args *dma_spec, ofdma->dma_router->route_free(ofdma->dma_router->dev, route_data); } else { + int ret = 0; + chan->router = ofdma->dma_router; chan->route_data = route_data; + + if (chan->device->device_router_config) + ret = chan->device->device_router_config(chan); + + if (ret) { + dma_release_channel(chan); + chan = ERR_PTR(ret); + } } /*
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index dd357a747780..d6197fe875af 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h@@ -800,6 +800,7 @@ struct dma_filter { * by tx_status * @device_alloc_chan_resources: allocate resources and return the * number of allocated descriptors + * @device_router_config: optional callback for DMA router configuration * @device_free_chan_resources: release DMA channel's resources * @device_prep_dma_memcpy: prepares a memcpy operation * @device_prep_dma_xor: prepares a xor operation
@@ -874,6 +875,7 @@ struct dma_device { enum dma_residue_granularity residue_granularity; int (*device_alloc_chan_resources)(struct dma_chan *chan); + int (*device_router_config)(struct dma_chan *chan); void (*device_free_chan_resources)(struct dma_chan *chan); struct dma_async_tx_descriptor *(*device_prep_dma_memcpy)(
--
Peter
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
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