From: Shravan Chippa <shravan.chippa@xxxxxxxxxxxxx> Update sf-pdma driver to adopt generic DMA device tree bindings. It calls of_dma_controller_register() with sf-pdma specific of_dma_xlate to get the generic DMA device tree helper support and the DMA clients can look up the sf-pdma controller using standard APIs. Signed-off-by: Shravan Chippa <shravan.chippa@xxxxxxxxxxxxx> --- drivers/dma/sf-pdma/sf-pdma.c | 44 +++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) diff --git a/drivers/dma/sf-pdma/sf-pdma.c b/drivers/dma/sf-pdma/sf-pdma.c index d1c6956af452..06a0912a12a1 100644 --- a/drivers/dma/sf-pdma/sf-pdma.c +++ b/drivers/dma/sf-pdma/sf-pdma.c @@ -20,6 +20,7 @@ #include <linux/mod_devicetable.h> #include <linux/dma-mapping.h> #include <linux/of.h> +#include <linux/of_dma.h> #include <linux/slab.h> #include "sf-pdma.h" @@ -490,6 +491,33 @@ static void sf_pdma_setup_chans(struct sf_pdma *pdma) } } +static struct dma_chan *sf_pdma_of_xlate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + struct sf_pdma *pdma = ofdma->of_dma_data; + struct device *dev = pdma->dma_dev.dev; + struct sf_pdma_chan *chan; + struct dma_chan *c; + u32 channel_id; + + if (dma_spec->args_count != 1) { + dev_err(dev, "Bad number of cells\n"); + return NULL; + } + + channel_id = dma_spec->args[0]; + + chan = &pdma->chans[channel_id]; + + c = dma_get_slave_channel(&chan->vchan.chan); + if (!c) { + dev_err(dev, "No more channels available\n"); + return NULL; + } + + return c; +} + static int sf_pdma_probe(struct platform_device *pdev) { struct sf_pdma *pdma; @@ -563,7 +591,20 @@ static int sf_pdma_probe(struct platform_device *pdev) return ret; } + ret = of_dma_controller_register(pdev->dev.of_node, + sf_pdma_of_xlate, pdma); + if (ret < 0) { + dev_err(&pdev->dev, + "Can't register SiFive Platform OF_DMA. (%d)\n", ret); + goto err_unregister; + } + return 0; + +err_unregister: + dma_async_device_unregister(&pdma->dma_dev); + + return ret; } static int sf_pdma_remove(struct platform_device *pdev) @@ -583,6 +624,9 @@ static int sf_pdma_remove(struct platform_device *pdev) tasklet_kill(&ch->err_tasklet); } + if (pdev->dev.of_node) + of_dma_controller_free(pdev->dev.of_node); + dma_async_device_unregister(&pdma->dma_dev); return 0; -- 2.34.1