Commit 65bf2205 authored by Geert Uytterhoeven's avatar Geert Uytterhoeven Committed by Mark Brown
Browse files

spi: rspi: Extract rspi_request_dma_chan() 



Setup of the receive and transmit DMA channels is very similar, so let's
consolidate.

Signed-off-by: default avatarGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: default avatarMark Brown <broonie@linaro.org>
parent 27e105a6

drivers/spi/spi-rspi.c

+55 −34
Original line number Diff line number Diff line
@@ -942,52 +942,73 @@ static irqreturn_t rspi_irq_tx(int irq, void *_sr) 
	return 0;

}



static struct dma_chan *rspi_request_dma_chan(struct device *dev,

					      enum dma_transfer_direction dir,

					      unsigned int id,

					      dma_addr_t port_addr)

{

	dma_cap_mask_t mask;

	struct dma_chan *chan;

	struct dma_slave_config cfg;

	int ret;



	dma_cap_zero(mask);

	dma_cap_set(DMA_SLAVE, mask);



	chan = dma_request_channel(mask, shdma_chan_filter,

				   (void *)(unsigned long)id);

	if (!chan) {

		dev_warn(dev, "dma_request_channel failed\n");

		return NULL;

	}



	memset(&cfg, 0, sizeof(cfg));

	cfg.slave_id = id;

	cfg.direction = dir;

	if (dir == DMA_MEM_TO_DEV)

		cfg.dst_addr = port_addr;

	else

		cfg.src_addr = port_addr;



	ret = dmaengine_slave_config(chan, &cfg);

	if (ret) {

		dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);

		dma_release_channel(chan);

		return NULL;

	}



	return chan;

}



static int rspi_request_dma(struct rspi_data *rspi,

			    struct platform_device *pdev)

{

	const struct rspi_plat_data *rspi_pd = dev_get_platdata(&pdev->dev);

	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	dma_cap_mask_t mask;

	struct dma_slave_config cfg;

	int ret;



	if (!res || !rspi_pd)

		return 0;	/* The driver assumes no error. */



	/* If the module receives data by DMAC, it also needs TX DMAC */

	if (rspi_pd->dma_rx_id && rspi_pd->dma_tx_id) {

		dma_cap_zero(mask);

		dma_cap_set(DMA_SLAVE, mask);

		rspi->chan_rx = dma_request_channel(mask, shdma_chan_filter,

						    (void *)rspi_pd->dma_rx_id);

		if (rspi->chan_rx) {

			cfg.slave_id = rspi_pd->dma_rx_id;

			cfg.direction = DMA_DEV_TO_MEM;

			cfg.dst_addr = 0;

			cfg.src_addr = res->start + RSPI_SPDR;

			ret = dmaengine_slave_config(rspi->chan_rx, &cfg);

			if (!ret)

		rspi->chan_rx = rspi_request_dma_chan(&pdev->dev,

						      DMA_DEV_TO_MEM,

						      rspi_pd->dma_rx_id,

						      res->start + RSPI_SPDR);

		if (!rspi->chan_rx)

			return -ENODEV;



		dev_info(&pdev->dev, "Use DMA when rx.\n");

			else

				return ret;

		}

	}

	if (rspi_pd->dma_tx_id) {

		dma_cap_zero(mask);

		dma_cap_set(DMA_SLAVE, mask);

		rspi->chan_tx = dma_request_channel(mask, shdma_chan_filter,

						    (void *)rspi_pd->dma_tx_id);

		if (rspi->chan_tx) {

			cfg.slave_id = rspi_pd->dma_tx_id;

			cfg.direction = DMA_MEM_TO_DEV;

			cfg.dst_addr = res->start + RSPI_SPDR;

			cfg.src_addr = 0;

			ret = dmaengine_slave_config(rspi->chan_tx, &cfg);

			if (!ret)

		rspi->chan_tx = rspi_request_dma_chan(&pdev->dev,

						      DMA_MEM_TO_DEV,

						      rspi_pd->dma_tx_id,

						      res->start + RSPI_SPDR);

		if (!rspi->chan_tx)

			return -ENODEV;



		dev_info(&pdev->dev, "Use DMA when tx\n");

			else

				return ret;

		}

	}



	return 0;