From mboxrd@z Thu Jan 1 00:00:00 1970 From: anton.bondarenko.sama@gmail.com (Anton Bondarenko) Date: Sun, 1 Nov 2015 15:41:41 +0100 Subject: [PATCH v3 7/7] spi: imx: defer spi initialization, if DMA engine is pending In-Reply-To: <1446388901-6073-1-git-send-email-anton.bondarenko.sama@gmail.com> References: <1446388901-6073-1-git-send-email-anton.bondarenko.sama@gmail.com> Message-ID: <1446388901-6073-8-git-send-email-anton.bondarenko.sama@gmail.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: Anton Bondarenko 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 Signed-off-by: Anton Bondarenko --- 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 6035ddd..d2ea731 100644 --- a/drivers/spi/spi-imx.c +++ b/drivers/spi/spi-imx.c @@ -1354,9 +1354,15 @@ 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_imx51_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_imx51_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); -- 2.6.2