[PATCH v2 7/8] spi: imx: defer spi initialization, if DMA engine is pending
Robin Gong
b38343 at freescale.com
Wed Sep 30 01:54:59 PDT 2015
On Fri, Sep 25, 2015 at 07:57:14PM +0200, Anton Bondarenko wrote:
> If SPI device supports DMA mode, but DMA controller is not yet
> available due to e.g. a delay in the corresponding kernel module
> initialization, retry to initialize SPI driver later on instead of
> falling back into PIO only mode.
>
> Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy at mentor.com>
> Signed-off-by: Anton Bondarenko <anton_bondarenko at mentor.com>
> ---
> drivers/spi/spi-imx.c | 12 +++++++++---
> 1 file changed, 9 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
> index 44d3cf0..1bf0739a 100644
> --- a/drivers/spi/spi-imx.c
> +++ b/drivers/spi/spi-imx.c
> @@ -1343,9 +1343,15 @@ static int spi_imx_probe(struct platform_device *pdev)
> * Only validated on i.mx6 now, can remove the constrain if validated on
> * other chips.
> */
> - if (is_imx5x_ecspi(spi_imx) &&
> - spi_imx_sdma_init(&pdev->dev, spi_imx, master))
> - dev_err(&pdev->dev, "dma setup error,use pio instead\n");
> + if (is_imx5x_ecspi(spi_imx)) {
> + ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
> + if (ret == -EPROBE_DEFER)
> + goto out_clk_put;
> +
> + if (ret < 0)
> + dev_err(&pdev->dev, "dma setup error %d, use pio\n",
> + ret);
> + }
>
> spi_imx->devtype_data->reset(spi_imx);
>
> --
> 2.5.2
>
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