From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matt Porter Subject: [RFC PATCH 10/13] spi: omap2-mcspi: dma_request_slave_channel() support for DT platforms Date: Thu, 20 Sep 2012 10:43:43 -0400 Message-ID: <1348152226-13588-11-git-send-email-mporter@ti.com> References: <1348152226-13588-1-git-send-email-mporter@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1348152226-13588-1-git-send-email-mporter-l0cyMroinI0@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: spi-devel-general-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org To: Tony Lindgren , Sekhar Nori , Grant Likely , Mark Brown , Benoit Cousson , Russell King , Vinod Koul , Rob Landley , Chris Ball Cc: Linux DaVinci Kernel List , Arnd Bergmann , Linux Documentation List , Devicetree Discuss , Linux MMC List , Linux Kernel Mailing List , Rob Herring , Dan Williams , Linux SPI Devel List , Linux OMAP List , Linux ARM Kernel List List-Id: devicetree@vger.kernel.org For platforms with DT populated, use dma_request_slave_channel() to acquire the DMA channel. For !DT platforms, we fall back to explicitly passing the omap_dma_filter_fn() to dma_request_channel(). Once all platforms boot from DT, the dma_request_channel() path can be dropped. Signed-off-by: Matt Porter --- drivers/spi/spi-omap2-mcspi.c | 68 +++++++++++++++++++++++++++++------------ 1 file changed, 48 insertions(+), 20 deletions(-) diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c index 9502566..1cf1072 100644 --- a/drivers/spi/spi-omap2-mcspi.c +++ b/drivers/spi/spi-omap2-mcspi.c @@ -104,6 +104,9 @@ struct omap2_mcspi_dma { struct completion dma_tx_completion; struct completion dma_rx_completion; + + char dma_rx_ch_name[14]; + char dma_tx_ch_name[14]; }; /* use PIO for small transfers, avoiding DMA setup/teardown overhead and @@ -798,14 +801,26 @@ static int omap2_mcspi_request_dma(struct spi_device *spi) dma_cap_zero(mask); dma_cap_set(DMA_SLAVE, mask); sig = mcspi_dma->dma_rx_sync_dev; - mcspi_dma->dma_rx = dma_request_channel(mask, omap_dma_filter_fn, &sig); + if (spi->dev.of_node) + mcspi_dma->dma_rx = + dma_request_slave_channel(&master->dev, + mcspi_dma->dma_rx_ch_name); + else + mcspi_dma->dma_rx = + dma_request_channel(mask, omap_dma_filter_fn, &sig); if (!mcspi_dma->dma_rx) { dev_err(&spi->dev, "no RX DMA engine channel for McSPI\n"); return -EAGAIN; } sig = mcspi_dma->dma_tx_sync_dev; - mcspi_dma->dma_tx = dma_request_channel(mask, omap_dma_filter_fn, &sig); + if (spi->dev.of_node) + mcspi_dma->dma_tx = + dma_request_slave_channel(&master->dev, + mcspi_dma->dma_tx_ch_name); + else + mcspi_dma->dma_tx = + dma_request_channel(mask, omap_dma_filter_fn, &sig); if (!mcspi_dma->dma_tx) { dev_err(&spi->dev, "no TX DMA engine channel for McSPI\n"); dma_release_channel(mcspi_dma->dma_rx); @@ -1194,29 +1209,42 @@ static int __devinit omap2_mcspi_probe(struct platform_device *pdev) goto free_master; for (i = 0; i < master->num_chipselect; i++) { - char dma_ch_name[14]; + char *dma_rx_ch_name = mcspi->dma_channels[i].dma_rx_ch_name; + char *dma_tx_ch_name = mcspi->dma_channels[i].dma_tx_ch_name; struct resource *dma_res; - sprintf(dma_ch_name, "rx%d", i); - dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA, - dma_ch_name); - if (!dma_res) { - dev_dbg(&pdev->dev, "cannot get DMA RX channel\n"); - status = -ENODEV; - break; - } + sprintf(dma_rx_ch_name, "rx%d", i); + if (!pdev->dev.of_node) { + dma_res = + platform_get_resource_byname(pdev, + IORESOURCE_DMA, + dma_rx_ch_name); + if (!dma_res) { + dev_dbg(&pdev->dev, + "cannot get DMA RX channel\n"); + status = -ENODEV; + break; + } - mcspi->dma_channels[i].dma_rx_sync_dev = dma_res->start; - sprintf(dma_ch_name, "tx%d", i); - dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA, - dma_ch_name); - if (!dma_res) { - dev_dbg(&pdev->dev, "cannot get DMA TX channel\n"); - status = -ENODEV; - break; + mcspi->dma_channels[i].dma_rx_sync_dev = + dma_res->start; } + sprintf(dma_tx_ch_name, "tx%d", i); + if (!pdev->dev.of_node) { + dma_res = + platform_get_resource_byname(pdev, + IORESOURCE_DMA, + dma_tx_ch_name); + if (!dma_res) { + dev_dbg(&pdev->dev, + "cannot get DMA TX channel\n"); + status = -ENODEV; + break; + } - mcspi->dma_channels[i].dma_tx_sync_dev = dma_res->start; + mcspi->dma_channels[i].dma_tx_sync_dev = + dma_res->start; + } } if (status < 0) -- 1.7.9.5 ------------------------------------------------------------------------------ Everyone hates slow websites. So do we. Make your web apps faster with AppDynamics Download AppDynamics Lite for free today: http://ad.doubleclick.net/clk;258768047;13503038;j? http://info.appdynamics.com/FreeJavaPerformanceDownload.html