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author | Geert Uytterhoeven <geert+renesas@glider.be> | 2014-06-02 15:38:09 +0200 |
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committer | Mark Brown <broonie@linaro.org> | 2014-06-02 15:49:33 +0100 |
commit | 65bf220571f131a7c3a564a88793bd0f16fd7c96 (patch) | |
tree | 112cd6651ff046bc62cba333ad01ee5c7bfdd857 /drivers/spi/spi-rspi.c | |
parent | 27e105a6006b8ce1b55709c5e24f63959981475d (diff) | |
download | linux-stable-65bf220571f131a7c3a564a88793bd0f16fd7c96.tar.gz linux-stable-65bf220571f131a7c3a564a88793bd0f16fd7c96.tar.bz2 linux-stable-65bf220571f131a7c3a564a88793bd0f16fd7c96.zip |
spi: rspi: Extract rspi_request_dma_chan()
Setup of the receive and transmit DMA channels is very similar, so let's
consolidate.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@linaro.org>
Diffstat (limited to 'drivers/spi/spi-rspi.c')
-rw-r--r-- | drivers/spi/spi-rspi.c | 89 |
1 files changed, 55 insertions, 34 deletions
diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c index 94a99ec7d989..0a7a2d618f0f 100644 --- a/drivers/spi/spi-rspi.c +++ b/drivers/spi/spi-rspi.c @@ -942,52 +942,73 @@ static irqreturn_t rspi_irq_tx(int irq, void *_sr) return 0; } -static int rspi_request_dma(struct rspi_data *rspi, - struct platform_device *pdev) +static struct dma_chan *rspi_request_dma_chan(struct device *dev, + enum dma_transfer_direction dir, + unsigned int id, + dma_addr_t port_addr) { - const struct rspi_plat_data *rspi_pd = dev_get_platdata(&pdev->dev); - struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0); dma_cap_mask_t mask; + struct dma_chan *chan; struct dma_slave_config cfg; int ret; + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + + chan = dma_request_channel(mask, shdma_chan_filter, + (void *)(unsigned long)id); + if (!chan) { + dev_warn(dev, "dma_request_channel failed\n"); + return NULL; + } + + memset(&cfg, 0, sizeof(cfg)); + cfg.slave_id = id; + cfg.direction = dir; + if (dir == DMA_MEM_TO_DEV) + cfg.dst_addr = port_addr; + else + cfg.src_addr = port_addr; + + ret = dmaengine_slave_config(chan, &cfg); + if (ret) { + dev_warn(dev, "dmaengine_slave_config failed %d\n", ret); + dma_release_channel(chan); + return NULL; + } + + return chan; +} + +static int rspi_request_dma(struct rspi_data *rspi, + struct platform_device *pdev) +{ + const struct rspi_plat_data *rspi_pd = dev_get_platdata(&pdev->dev); + struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res || !rspi_pd) return 0; /* The driver assumes no error. */ /* If the module receives data by DMAC, it also needs TX DMAC */ if (rspi_pd->dma_rx_id && rspi_pd->dma_tx_id) { - dma_cap_zero(mask); - dma_cap_set(DMA_SLAVE, mask); - rspi->chan_rx = dma_request_channel(mask, shdma_chan_filter, - (void *)rspi_pd->dma_rx_id); - if (rspi->chan_rx) { - cfg.slave_id = rspi_pd->dma_rx_id; - cfg.direction = DMA_DEV_TO_MEM; - cfg.dst_addr = 0; - cfg.src_addr = res->start + RSPI_SPDR; - ret = dmaengine_slave_config(rspi->chan_rx, &cfg); - if (!ret) - dev_info(&pdev->dev, "Use DMA when rx.\n"); - else - return ret; - } + rspi->chan_rx = rspi_request_dma_chan(&pdev->dev, + DMA_DEV_TO_MEM, + rspi_pd->dma_rx_id, + res->start + RSPI_SPDR); + if (!rspi->chan_rx) + return -ENODEV; + + dev_info(&pdev->dev, "Use DMA when rx.\n"); } if (rspi_pd->dma_tx_id) { - dma_cap_zero(mask); - dma_cap_set(DMA_SLAVE, mask); - rspi->chan_tx = dma_request_channel(mask, shdma_chan_filter, - (void *)rspi_pd->dma_tx_id); - if (rspi->chan_tx) { - cfg.slave_id = rspi_pd->dma_tx_id; - cfg.direction = DMA_MEM_TO_DEV; - cfg.dst_addr = res->start + RSPI_SPDR; - cfg.src_addr = 0; - ret = dmaengine_slave_config(rspi->chan_tx, &cfg); - if (!ret) - dev_info(&pdev->dev, "Use DMA when tx\n"); - else - return ret; - } + rspi->chan_tx = rspi_request_dma_chan(&pdev->dev, + DMA_MEM_TO_DEV, + rspi_pd->dma_tx_id, + res->start + RSPI_SPDR); + if (!rspi->chan_tx) + return -ENODEV; + + dev_info(&pdev->dev, "Use DMA when tx\n"); } return 0; |