Unverified Commit 6133fed0 authored by Peter Ujfalusi's avatar Peter Ujfalusi Committed by Mark Brown
Browse files

spi: bcm2835: Use dma_request_chan() instead dma_request_slave_channel() 



dma_request_slave_channel() is a wrapper on top of dma_request_chan()
eating up the error code.

By using dma_request_chan() directly the driver can support deferred
probing against DMA.

Signed-off-by: default avatarPeter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20191212135550.4634-4-peter.ujfalusi@ti.com


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 666224b4

drivers/spi/spi-bcm2835.c

+24 −10
Original line number Diff line number Diff line
@@ -888,7 +888,7 @@ static void bcm2835_dma_release(struct spi_controller *ctlr, 
	}

}



static void bcm2835_dma_init(struct spi_controller *ctlr, struct device *dev,

static int bcm2835_dma_init(struct spi_controller *ctlr, struct device *dev,

			    struct bcm2835_spi *bs)

{

	struct dma_slave_config slave_config;
@@ -900,19 +900,24 @@ static void bcm2835_dma_init(struct spi_controller *ctlr, struct device *dev, 
	addr = of_get_address(ctlr->dev.of_node, 0, NULL, NULL);

	if (!addr) {

		dev_err(dev, "could not get DMA-register address - not using dma mode\n");

		goto err;

		/* Fall back to interrupt mode */

		return 0;

	}

	dma_reg_base = be32_to_cpup(addr);



	/* get tx/rx dma */

	ctlr->dma_tx = dma_request_slave_channel(dev, "tx");

	if (!ctlr->dma_tx) {

	ctlr->dma_tx = dma_request_chan(dev, "tx");

	if (IS_ERR(ctlr->dma_tx)) {

		dev_err(dev, "no tx-dma configuration found - not using dma mode\n");

		ret = PTR_ERR(ctlr->dma_tx);

		ctlr->dma_tx = NULL;

		goto err;

	}

	ctlr->dma_rx = dma_request_slave_channel(dev, "rx");

	if (!ctlr->dma_rx) {

	ctlr->dma_rx = dma_request_chan(dev, "rx");

	if (IS_ERR(ctlr->dma_rx)) {

		dev_err(dev, "no rx-dma configuration found - not using dma mode\n");

		ret = PTR_ERR(ctlr->dma_rx);

		ctlr->dma_rx = NULL;

		goto err_release;

	}
@@ -997,7 +1002,7 @@ static void bcm2835_dma_init(struct spi_controller *ctlr, struct device *dev, 
	/* all went well, so set can_dma */

	ctlr->can_dma = bcm2835_spi_can_dma;



	return;

	return 0;



err_config:

	dev_err(dev, "issue configuring dma: %d - not using DMA mode\n",
@@ -1005,7 +1010,14 @@ err_config: 
err_release:

	bcm2835_dma_release(ctlr, bs);

err:

	return;

	/*

	 * Only report error for deferred probing, otherwise fall back to

	 * interrupt mode

	 */

	if (ret != -EPROBE_DEFER)

		ret = 0;



	return ret;

}



static int bcm2835_spi_transfer_one_poll(struct spi_controller *ctlr,
@@ -1317,7 +1329,9 @@ static int bcm2835_spi_probe(struct platform_device *pdev) 


	clk_prepare_enable(bs->clk);



	bcm2835_dma_init(ctlr, &pdev->dev, bs);

	err = bcm2835_dma_init(ctlr, &pdev->dev, bs);

	if (err)

		goto out_clk_disable;



	/* initialise the hardware with the default polarities */

	bcm2835_wr(bs, BCM2835_SPI_CS,

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