diff options
Diffstat (limited to 'drivers/spi/spi-bcm2835.c')
| -rw-r--r-- | drivers/spi/spi-bcm2835.c | 47 |
1 files changed, 33 insertions, 14 deletions
diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c index fb61a620effc..11c235879bb7 100644 --- a/drivers/spi/spi-bcm2835.c +++ b/drivers/spi/spi-bcm2835.c @@ -68,7 +68,7 @@ #define BCM2835_SPI_FIFO_SIZE 64 #define BCM2835_SPI_FIFO_SIZE_3_4 48 #define BCM2835_SPI_DMA_MIN_LENGTH 96 -#define BCM2835_SPI_NUM_CS 3 /* raise as necessary */ +#define BCM2835_SPI_NUM_CS 4 /* raise as necessary */ #define BCM2835_SPI_MODE_BITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \ | SPI_NO_CS | SPI_3WIRE) @@ -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, @@ -1305,7 +1317,10 @@ static int bcm2835_spi_probe(struct platform_device *pdev) bs->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(bs->clk)) { err = PTR_ERR(bs->clk); - dev_err(&pdev->dev, "could not get clk: %d\n", err); + if (err == -EPROBE_DEFER) + dev_dbg(&pdev->dev, "could not get clk: %d\n", err); + else + dev_err(&pdev->dev, "could not get clk: %d\n", err); goto out_controller_put; } @@ -1317,7 +1332,9 @@ 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, @@ -1327,20 +1344,22 @@ static int bcm2835_spi_probe(struct platform_device *pdev) dev_name(&pdev->dev), ctlr); if (err) { dev_err(&pdev->dev, "could not request IRQ: %d\n", err); - goto out_clk_disable; + goto out_dma_release; } err = devm_spi_register_controller(&pdev->dev, ctlr); if (err) { dev_err(&pdev->dev, "could not register SPI controller: %d\n", err); - goto out_clk_disable; + goto out_dma_release; } bcm2835_debugfs_create(bs, dev_name(&pdev->dev)); return 0; +out_dma_release: + bcm2835_dma_release(ctlr, bs); out_clk_disable: clk_disable_unprepare(bs->clk); out_controller_put: |