From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robin Gong Subject: Re: [PATCH v2 7/8] spi: imx: defer spi initialization, if DMA engine is pending Date: Wed, 30 Sep 2015 16:54:59 +0800 Message-ID: <20150930085458.GG2709@shlinux2> References: <42b82309e539e8a5523dca5364846c472ab9dcee.1442923630.git.anton_bondarenko@mentor.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: muzaffar_mahmood@relay1.mentorg.com, jiada_wang@mentor.com, linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org, broonie@kernel.org, vladimir_zapolskiy@mentor.com, linux-arm-kernel@lists.infradead.org To: Anton Bondarenko Return-path: Content-Disposition: inline In-Reply-To: <42b82309e539e8a5523dca5364846c472ab9dcee.1442923630.git.anton_bondarenko@mentor.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org List-Id: linux-spi.vger.kernel.org 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 > 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 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 >