diff options
| author | Peter Ujfalusi <peter.ujfalusi@ti.com> | 2019-12-12 16:55:44 +0300 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2019-12-16 14:56:46 +0300 |
| commit | 6133fed0539bc5c059d3a661b61704159ba448a6 (patch) | |
| tree | b6cd62e1c4fb8a0b4a241990277137159207d8c4 /drivers/spi/spi-bcm2835.c | |
| parent | 666224b43b4bd4612ce3b758c038f9bc5c5e3fcb (diff) | |
| download | linux-6133fed0539bc5c059d3a661b61704159ba448a6.tar.xz | |
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: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20191212135550.4634-4-peter.ujfalusi@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi/spi-bcm2835.c')
| -rw-r--r-- | drivers/spi/spi-bcm2835.c | 34 |
1 files changed, 24 insertions, 10 deletions
diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c index 662d55e9f21d..69df79914504 100644 --- a/drivers/spi/spi-bcm2835.c +++ b/drivers/spi/spi-bcm2835.c @@ -888,8 +888,8 @@ static void bcm2835_dma_release(struct spi_controller *ctlr, } } -static void bcm2835_dma_init(struct spi_controller *ctlr, struct device *dev, - struct bcm2835_spi *bs) +static int bcm2835_dma_init(struct spi_controller *ctlr, struct device *dev, + struct bcm2835_spi *bs) { struct dma_slave_config slave_config; const __be32 *addr; @@ -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, |