Add generic DMA bindings and register the DMA controller to DT DMA helpers.
Signed-off-by: Anatolij Gustschin <[email protected]> --- arch/powerpc/boot/dts/mpc5121.dtsi | 5 ++- drivers/dma/mpc512x_dma.c | 63 ++++++++++++++++++++++++++++++++++-- 2 files changed, 64 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/boot/dts/mpc5121.dtsi b/arch/powerpc/boot/dts/mpc5121.dtsi index 723e292..d1fe070 100644 --- a/arch/powerpc/boot/dts/mpc5121.dtsi +++ b/arch/powerpc/boot/dts/mpc5121.dtsi @@ -384,10 +384,13 @@ interrupts = <40 0x8>; }; - dma@14000 { + dma0: dma@14000 { compatible = "fsl,mpc5121-dma"; reg = <0x14000 0x1800>; interrupts = <65 0x8>; + #dma-cells = <1>; + #dma-channels = <64>; + #dma-requests = <64>; }; }; diff --git a/drivers/dma/mpc512x_dma.c b/drivers/dma/mpc512x_dma.c index 2d95673..bc6c356 100644 --- a/drivers/dma/mpc512x_dma.c +++ b/drivers/dma/mpc512x_dma.c @@ -40,6 +40,7 @@ #include <linux/io.h> #include <linux/slab.h> #include <linux/of_device.h> +#include <linux/of_dma.h> #include <linux/of_platform.h> #include <linux/random.h> @@ -641,6 +642,44 @@ mpc_dma_prep_memcpy(struct dma_chan *chan, dma_addr_t dst, dma_addr_t src, return &mdesc->desc; } +struct mpc_dma_filter_args { + struct mpc_dma *mdma; + unsigned int chan_id; +}; + +static bool mpc_dma_filter(struct dma_chan *chan, void *param) +{ + struct mpc_dma_filter_args *fargs = param; + + if (chan->device != &fargs->mdma->dma) + return false; + + return (chan->chan_id == fargs->chan_id); +} + +static struct dma_chan *mpc_dma_xlate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + int count = dma_spec->args_count; + struct mpc_dma *mdma = ofdma->of_dma_data; + struct mpc_dma_filter_args fargs; + dma_cap_mask_t cap; + + if (!mdma) + return NULL; + + if (count != 1) + return NULL; + + fargs.mdma = mdma; + fargs.chan_id = dma_spec->args[0]; + + dma_cap_zero(cap); + dma_cap_set(DMA_SLAVE, cap); + + return dma_request_channel(cap, mpc_dma_filter, &fargs); +} + static int mpc_dma_probe(struct platform_device *op) { struct device_node *dn = op->dev.of_node; @@ -791,11 +830,26 @@ static int mpc_dma_probe(struct platform_device *op) /* Register DMA engine */ dev_set_drvdata(dev, mdma); retval = dma_async_device_register(dma); - if (retval) { - devm_free_irq(dev, mdma->irq, mdma); - irq_dispose_mapping(mdma->irq); + if (retval) + goto reg_err; + + if (dev->of_node) { + retval = of_dma_controller_register(dev->of_node, + mpc_dma_xlate, mdma); + if (retval) { + dev_err(&op->dev, + "could not register of_dma_controller\n"); + goto of_err; + } } + return 0; + +of_err: + dma_async_device_unregister(&mdma->dma); +reg_err: + devm_free_irq(dev, mdma->irq, mdma); + irq_dispose_mapping(mdma->irq); return retval; } @@ -804,6 +858,9 @@ static int mpc_dma_remove(struct platform_device *op) struct device *dev = &op->dev; struct mpc_dma *mdma = dev_get_drvdata(dev); + if (dev->of_node) + of_dma_controller_free(dev->of_node); + dma_async_device_unregister(&mdma->dma); devm_free_irq(dev, mdma->irq, mdma); irq_dispose_mapping(mdma->irq); -- 1.7.5.4 _______________________________________________ devicetree-discuss mailing list [email protected] https://lists.ozlabs.org/listinfo/devicetree-discuss
