On Sat, Jul 27, 2013 at 03:27:58AM +0800, Stephen Warren wrote: > (Stripping the Cc list a lot) > > On 07/23/2013 10:09 PM, Richard Zhao wrote: > > Update tegra20-apbdma driver to adopt generic DMA device tree bindings. > > It calls of_dma_controller_register() with of_dma_simple_xlate to get > > the generic DMA device tree helper support. The #dma-cells for apbdma > > must be 1, which is slave ID. > > > > The existing nvidia,dma-request-selector still works there, and the > > support will be removed after all clients get converted to generic DMA > > device tree helper. > > (BTW, I would like to take this series through the Tegra tree to > simplify dependencies. So, I'm looking for ack's on the drivers rather > than for them to be applied. I had hoped Richard would point this out > when posting the patches) Sorry I forgot to add maintainr-pick-up suggestions. > > > diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c > > > +static bool tegra_dma_filter_fn(struct dma_chan *dc, void *param) > > +{ > > + if (dc->device->dev->driver == &tegra_dmac_driver.driver) { > > + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); > > + unsigned req = *(unsigned *)param; > > + > > + tdc->slave_id = req; > > + > > + return true; > > + } > > + return false; > > +} > > + > > +static struct of_dma_filter_info tegra_dma_info = { > > + .filter_fn = tegra_dma_filter_fn, > > +}; > > Why does this driver need to define a filter function? I thought the > dmaengine's DT support would already match DMA clients/engines based on > the phandle in DT? Isn't the need to pass the slave channel ID into > drivers something pretty fundamental to dmaengine, and hence something > it already supports? of_dma_simple_xlate only pass slave id to filter function. It needs change to pass dt node too. I didn't start work on the common code change yet. Do you think we need to hold it until common code change? Thanks Richard > -- > To unsubscribe from this list: send the line "unsubscribe linux-tegra" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html